Obesity and Diabetes: Scientific Advances and Best Practice [2 ed.] 3030533697, 9783030533694

Citation preview

Joel Faintuch Salomão Faintuch   Editors

Obesity and Diabetes Scientific Advances and Best Practice Second Edition

Obesity and Diabetes

Joel Faintuch • Salomão Faintuch Editors

Obesity and Diabetes Scientific Advances and Best Practice Second Edition

Editors Joel Faintuch Hospital das Clinicas Sao Paulo University Medical School Sao Paulo, Brazil

Salomão Faintuch Harvard Medical School Beth Israel Deaconess Medical Center Boston, MA, USA

ISBN 978-3-030-53369-4 ISBN 978-3-030-53370-0 https://doi.org/10.1007/978-3-030-53370-0

(eBook)

# Springer Nature Switzerland AG 2020 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors, and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. This Springer imprint is published by the registered company Springer Nature Switzerland AG. The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

Foreword

Obesity and diabetes mellitus are two interrelated, chronic, debilitating, incurable diseases that have increased in incidence worldwide. In the USA, over 60% of adult Americans are overweight or obese. Most countries around the world are also seeing dramatically increasing rates of obesity. Although not all people with type 2 diabetes are overweight or obese, the majority are. In addition, while most individuals who suffer from obesity are not diabetic, the incidence of T2DM increases as adiposity increases. So intertwined are these seemingly independent metabolic disorders that some refer to them together as “diabesity.” Despite spending billions of dollars on research and the development of a multitude of different treatments, we have failed to control either disease and find ourselves heading off the cliff. While there has been an explosion of new medications, surgical procedures, and the introduction of metabolic/bariatric devices, the incidence of both diseases continues to rise. It has been estimated that within a few short years, the cost to treat the various related medical conditions of these two diseases will be financially unsustainable for most countries. To better manage this impending crisis, clinicians and researchers need to broaden our understanding of the pathophysiology of both diabetes and obesity. It is far too simplistic to blame patient behavior, societal pressures, or the environment for the epidemic. One must consider other possibilities as well. Recently, researchers have taken a closer look at potential causes or contributors such as bile salt composition, genomics, microbiomes, inflammation, and the deep brain. A better understanding of the pathophysiology is necessary to guide the development of more efficacious and cost-effective treatments. In addition, to be the most beneficial, the research findings need to be properly organized and be available worldwide. This new book entitled, Obesity and Diabetes, edited by Joel Faintuch, MD, a surgeon and a highly regarded nutrition support specialist, and Salomao Faintuch, MD, a Harvard Director of Interventional Radiology, should accomplish these goals. The book is extremely thorough and very well organized. Its nine sections (blocks) cover a wide range of current and cutting-edge information from the epidemiology of diabetes and obesity to bariatric and metabolic surgery to treat both disorders. The blocks and chapters of the book are strategically organized. They begin with basic science and epidemiologic chapters and conclude with clinical treatments and v

vi

Foreword

ongoing developments. As previously stated, we as a human race cannot continue as we have, partially understanding and inadequately managing obesity and diabetes mellitus. We cannot sustain the costs nor the effects on health and quality of life. Obesity and Diabetes may become a valuable tool for researchers and clinicians alike. Harvard Medical School, Center for Metabolic and Bariatric Surgery, Brigham and Women's Hospital, Boston, MA, USA

Scott A. Shikora

Preface

About 6 years ago, the first edition of this book was being organized. At that time, obesity and diabetes were already counted among the leading non-communicable diseases in the world; however, the global burden had not been elucidated yet. As underscored in the current Introduction chapter, the figures were soon unearthed: USD2 trillion for obesity in 2014 and USD1.3 trillion for diabetes (2015), summing up to USD3.3 trillion. Only major addictions fluctuate in the same range. If one adds up the values for smoking (USD2.1 trillion) and alcoholism (USD1.4 trillion), the total will reach USD3.5 trillion. However, one should consider that whereas alcoholism is a mounting concern, the smokers’ curve is receding in many countries, and could turn flat in the coming decades. Metabolic diseases in turn, with obesity and diabetes spearheading the trend, continue to grow unabatedly, so that it is projected that half of the world will be overweight or obese by 2030. No other disease group comes close. Does that mean that medical schools should sidestep gastroenterology, rheumatology, and gynecology, concentrating instead on obesity/diabetes, and prevention of substance abuse (interspersed with classes on emerging infectious epidemics)? The healthcare domain is not that much utilitarian. Results-based performance management is important; however, it does not supersede the requirements for a global technical and scientific professional background. Moreover, one is not allowed to forget the ethical commitment toward the patient as an integral human being, not as a collection of disease labels. All these factors notwithstanding, practically all specialties will be touched, if not overwhelmed by the new scenario. Orthopedists are already having difficulty to cope with knees and hips damaged by excessive body weight, whereas ophthalmologists, nephrologists, neurologists, and even pediatricians are facing a deluge of diabetics in their daily practice, to mention just a few examples. The same is true for the allied healthcare professions. Becoming familiar with the intricacies of obesity and diabetes is a must for nurses, psychologists, dietitians, hospital social workers, and specialists in biomedical engineering, given the sheer numbers of this population. Of course, the commonalities as well as the diversities of the illnesses need to be understood, from the vantage point of new achievements in an array of fields, from drug therapy to bariatric and metabolic surgery, and from appetite control to artificial pancreas. Among the cutting-edge science highlights of this edition, omics biomarkers originated from genomic, metabolomic, and immunologic profiling are vii

viii

Preface

dissected within the framework of diagnosis, disease monitoring, prognosis, and new therapeutic targets, in obesity and diabetes. Anti-obesity vaccines ? Outlandish and whimsical as they may sound, and past false starts notwithstanding, there are robust experimental investigation lines in this arena. Similarly microbiomic pathways and signatures are becoming indispensable in the assessment and follow-up of metabolic diseases and treatments. There is compelling evidence that part of the surgical response to bariatric and metabolic procedures is microbiome dependent, analogously to an array of other treatments and circumstances. Both type 1 and 2 diabetes are benefitting from genetic sequencing and immune profiling, with results which can be harnessed for diagnostic and therapeutic purposes. Bariatric and endoscopic interventions are in rapid mutation, including robotic platforms and innovative approaches, as described by respected authorities. Cell therapy and nanoparticle carriers are put into context. Public health initiatives were not neglected either. From governmentmandated taxes for unhealthy foods to scrutinized school canteen menus and the contrast between personalized dietetic counseling and general guidance for the population, including Internet-based initiatives, smartphones, and wearable devices, no stone was left unturned in the effort to bring the latest and most practical information. Sao Paulo, Brazil Boston, MA, USA

Joel Faintuch Salomão Faintuch

Contents

Part I 1

2

Epidemiology, Inheritance, Environment and Pathways

Introduction to Obesity and Diabetes: The Windows of Opportunity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Joel Faintuch and Salomao Faintuch Nutrition Transition and Obesity Trends in Argentina Within the Latin American Context . . . . . . . . . . . . . . . . . . . . Sonia Alejandra Pou, Natalia Tumas, and Laura Rosana Aballay

3

9

3

Challenges and Economic Burden of Diabetes in Africa . . . . . Camille Maadjhou Mba and Jean Claude Mbanya

21

4

Brown Adipose Tissue in Obesity and Diabetes . . . . . . . . . . . Martín Alcalá, Laura Herrero, Dolors Serra, and Marta Viana

35

5

White and Brown Adipose Tissue in Obesity and Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Brooks P. Leitner and Borja Martinez-Tellez

6

microRNAs in Obesity and Metabolic Diseases . . . . . . . . . . . Giuseppe Iacomino, Fabio Lauria, Antonella Venezia, Nunzia Iannaccone, Paola Russo, and Alfonso Siani

7

From Adipogenic Viruses to Antidiabetic Drug: A Translational Journey . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vijay Hegde and Nikhil V. Dhurandhar

55 71

97

8

Genetic Profiles in the Obese Population . . . . . . . . . . . . . . . . 107 Ana Carolina Proença da Fonseca, Patrícia Torres Bozza, and Pedro Hernán Cabello

9

The Upstream Environment for the Obesity Epidemic . . . . . . 127 Peter Congdon

10

Inflammation and Its Role in Obesity-Related Complications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 Mohit Singh, Jiten R. Sharma, Hina Agraval, and Umesh C. S. Yadav

ix

x

Contents

11

Crosstalk Between Adipose Tissue, Macrophages, and Other Immune Cells: Development of Obesity and Inflammationinduced Metabolic Diseases . . . . . . . . . . . . . . . . . . . . . . . . . . 151 Rohit Patel, Johnna Francis Varghese, and Umesh Chand Singh Yadav

12

Diabetes Forecasts and Statistics for the Coming Decades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 Alexandre Assuane Duarte and Olga Golubnitschaja

13

Pancreatic Islets of Langerhans: Adapting Cell and Molecular Biology to Changes of Metabolism . . . . . . . . . . . . . . . . . . . . . 175 Fernanda Ornellas, Iara Karise, Marcia Barbosa Aguila, and Carlos Alberto Mandarim-de-Lacerda

14

Targeting Advanced Glycation End Products (esRAGE and sRAGE) for Obesity, Diabetes, and its Associated Complications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191 Chinedum Eleazu and Mahaneem Mohamed

15

Anti-incretin Effect: A Missing Link between Obesity, Diabetes, and Metabolic Surgery . . . . . . . . . . . . . . . . . . . . . . 199 Theocharis Koufakis, Spyridon N. Karras, and Kalliopi Kotsa

Part II

Genomics, Metabolomics and Other Omics

16

An Update on Mendelian Forms of Obesity and their Personalized Treatments . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207 Selene Chen and David Meyre

17

The Genetic Basis of Diabetic Kidney Disease . . . . . . . . . . . . 221 Christopher A. Simeone, Jose M. Lazaro-Guevara, and Marcus G. Pezzolesi

18

Epigenetics and Chronic Inflammation: Role in Early Detection of Type 2 Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . 237 Meenu Ghai

19

Salivary and Urinary Metabolome in Pediatric Obesity and Metabolic Syndrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 Jacopo Troisi, Francesca Marciano, Giovanni Scala, Elizabeth Plunk, Luca Pierri, and Angelo Colucci

20

‘State-of-the-Art’ Metabolomics Investigations of Type 2 Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 Benita Percival, Justine Leenders, and Martin Grootveld

21

The Gut Microbiome and Type 2 Diabetes Mellitus . . . . . . . . 283 Shruti Panwar, Samriddhi Arora, Sapna Sharma, and Prabhanshu Tripathi

22

Immunotherapeutic Approach to the Treatment and Prevention of Obesity . . . . . . . . . . . . . . . . . . . . . . . . . . . 297 Tatsuhiko Azegami and Hiroshi Itoh

Contents

xi

Part III

Associated Disorders and Obesity Paradoxes

23

Metabolic Syndrome Update . . . . . . . . . . . . . . . . . . . . . . . . . 305 Uzma Zafar

24

Non-alcoholic Fatty Liver Disease: A Global Public Health Issue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321 Eda Kaya and Yusuf Yilmaz

25

Nonalcoholic Fatty Pancreatic Disease (NAFPD) . . . . . . . . . . 335 Alhareth Al Juboori, Harleen Chela, Sami Samiullah, and Veysel Tahan

26

Normal-weight Obesity: A Hidden Pandemic . . . . . . . . . . . . . 347 Shajith Anoop and Nitin Kapoor

27

Obesity in Children/Adolescents and Obesity-Related Comorbidities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361 Taisa Kohut, Jennifer Robbins, Elizabeth Prout, Lorraine Katz, Julie Brothers, Kimberly Genuario, and Jennifer Panganiban

28

Obesity and Cancer: Linked Molecular Mechanisms . . . . . . . 385 Erika Di Zazzo, Monica Rienzo, Maria Michela Marino, Donatella Fiore, Chiara Piscopo, Amelia Casamassimi, Bruno Moncharmont, and Ciro Abbondanza

29

Cognitive Impairment in Obesity and Diabetes . . . . . . . . . . . 399 Cristina Carvalho and Paula I. Moreira

30

Metabolic Pathways Underlying Neuropsychiatric Disorders and Obesity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 415 Laís Bhering Martins, Silvia Fernandes Mauricio, Adaliene Versiani Matos Ferreira, and Antônio Lúcio Teixeira

31

Heart Failure and the Obesity Paradox . . . . . . . . . . . . . . . . . 427 Marijana Tadic and Cesare Cuspidi

32

Inflammatory Mechanisms in Diabetic Kidney Disease . . . . . 437 Radica Z. Alicic, Emily J. Cox, Joshua J. Neumiller, and Katherine R. Tuttle

33

The Epidemiology of the Diabetes: Depression Comorbidity in Brazil—Inequality and Interaction . . . . . . . . . . . . . . . . . . . 457 Finn Diderichsen

34

Contribution of Hyperglycemia and Unhealthy Diet to Cardiovascular Mortality . . . . . . . . . . . . . . . . . . . . . . . . . . . . 471 Jian Zhang and Dong Li

35

Gestational Diabetes Mellitus . . . . . . . . . . . . . . . . . . . . . . . . . 479 Elpida Vounzoulaki and Samuel Seidu

36

Update on Gestational Diabetes . . . . . . . . . . . . . . . . . . . . . . . 493 Megan Jones and Allison Akers

xii

37

Contents

Vascular Complications in Type 2 Diabetes . . . . . . . . . . . . . . 509 Chih Hao Chen Ku

Part IV

General Therapy and Prevention

38

What We Know and Don’t About High-Intensity Sweeteners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 529 Clipper F. Young, Anne Lee, and Joy Dugan

39

Personalised Molecular Feedback for Weight Loss . . . . . . . . . 541 Shilpa Tejpal

40

Diabetes and Obesity in the Child and Adolescent: Guidelines and Challenges . . . . . . . . . . . . . . . . . . . . . . . . . . . 553 Suzanne Cuda and Marisa Censani

41

Type 2 Diabetes: An Unresolved Disease . . . . . . . . . . . . . . . . 567 Sarah Cuschieri

42

Glucose Control in the Intensive Care Unit . . . . . . . . . . . . . . 579 Jan Gunst and Greet Van den Berghe

43

Continuous Glucose Monitors as Wearable Lifestyle Behavior Change Tools in Obesity and Diabetes . . . . . . . . . . 591 Susan M. Schembre

Part V Innovative Endoscopic, Cell Therapy and Other Interventions 44

Endoscopic Techniques for Obesity and Diabetes . . . . . . . . . . 607 Vitor Ottoboni Brunaldi, João Almiro Ferreira Filho, and Daniel Martone

45

Bariatric Embolization: A Possible Non-surgical Option for Weight Reduction . . . . . . . . . . . . . . . . . . . . . . . . . 619 Muhammad A. Latif and Clifford R. Weiss

46

Progress in Noninvasive Beta-Cell Mass Imaging . . . . . . . . . . 631 Bluma Linkowski Faintuch and Salomao Faintuch

47

Cancer Staging with 18F-FDG PET/CT in Hyperglycemic Patients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641 Monica Finessi, Virginia Liberini, and Désirée Deandreis

48

Pancreatic Islet Transplantation: A Surgical Approach to Type 1 Diabetes Treatment . . . . . . . . . . . . . . . . . . . . . . . . 655 Samuel Rodriguez, Michael Alexander, and Jonathan R. T. Lakey

49

Pancreatic Transplantation in Diabetes: Indications, Contraindications and Perspectives . . . . . . . . . . . . . . . . . . . . 665 Vinicius Rocha-Santos and Carlos Andres Pantanali

Contents

xiii

Part VI

Pharmacological Therapy and Cost Containment

50

Pharmacotherapy of Type 2 Diabetes . . . . . . . . . . . . . . . . . . . 679 Jaskiran Kaur, Paras Famta, Navneet Khurana, Manish Vyas, and Gopal L. Khatik

51

GLP1-Receptor Agonists in Diabetes: Drugs, General Effects, and Cardiovascular Impact . . . . . . . . . . . . . . . . . . . . . . . . . . 695 Ikaro Breder and Andrei C. Sposito

52

Diabetes and Treatments . . . . . . . . . . . . . . . . . . . . . . . . . . . . 705 Milan Obradovic, Emina Sudar-Milovanovic, Zoran Gluvic, Takashi Gojobori, Magbubah Essack, and Esma R. Isenovic

53

Treatment of Diabetes and Heart Failure . . . . . . . . . . . . . . . . 719 Bradley Brochu and Michael Chan

54

Cardiovascular Impact of Newer Diabetes Medications . . . . . 735 Ravi Kant, Mc Anto Antony, Arshpreet Kaur, Nathan A. Gilreath, Rashmi Chandra, and Vipin Verma

55

Pathogenesis and Molecular Targets in Treatment of Diabetic Wounds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 747 Satish Patel, Pragati, Shradha Devi Dwivedi, Krishna Yadav, Jagat R. Kanwar, Manju Rawat Singh, and Deependra Singh

56

Efficiency in Public Health Through the Promotion of Diabetes Day Hospitals: A Regional Proposal . . . . . . . . . . 759 Ascensión Barroso, Ramón Sanguino, Victoria Barroso, and M. Isabel Sánchez-Hernández

Part VII

Bariatric and Metabolic Surgery

57

Surgical Options in Obesity and Diabetes . . . . . . . . . . . . . . . . 767 Jaime Ruiz-Tovar and Lorea Zubiaga

58

One Anastomosis Gastric Bypass in the Treatment of Obesity: Effects on Body Weight and the Metabolome . . . . . . . . . . . . . 777 Adriana Mika, Tomasz Sledzinski, Monika Proczko-Stepaniak, and Faidon Magkos

59

Robotic Bariatric Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . 791 Candice Silverman, Anna Isaacs, and Nan Guang Tan

60

The Role of Obesity and Bariatric Surgery in the Management of Knee and Hip Osteoarthritis . . . . . . . . . . . . . 813 Katelyn M. Mellion and Shanu N. Kothari

61

Relapse of Diabetes After Metabolic/Bariatric Surgery . . . . . 827 Lívia Porto Cunha da Silveira, Tarissa Zanata Petry, and Ricardo Vitor Cohen

62

Malnutrition in Obesity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 835 Sonmoon Mohapatra and Capecomorin S. Pitchumoni

xiv

Contents

Part VIII New Apps, Drugs, Artificial Intelligence and Public Health Initiatives 63

Sugar-Sweetened Beverage Taxes: Origins, Mechanisms, and Current Worldwide Status . . . . . . . . . . . . . . . . . . . . . . . 851 Fabrizio Ferretti

64

Mobile Health Interventions for Weight Management in Overweight and Obese Populations . . . . . . . . . . . . . . . . . . . . 865 Lynnette Lyzwinski

65

Biomarkers and Machine Learning Applications in Obesity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 883 Olga Tsave and Ioannis Kavakiotis

66

Current Approaches in Diabetes Mellitus Prediction: Applications of Machine Learning and Emerging Biomarkers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 893 Sergey A. Solodskikh, Vladimir M. Dudenkov, Viktor Yu. Glanz, Anna V. Panevina, Vasily N. Popov, and Alexey S. Velikorodny

67

Lifestyle Interventions for Sarcopenic Obesity in Polycystic Ovary Syndrome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 907 Philip D. Chilibeck, Maryam Kazemi, Laura E. McBreairty, and Gordon A. Zello

68

Drug Pipeline for Obesity Therapy . . . . . . . . . . . . . . . . . . . . 921 Azania T. Panicker, Priyanshi Desai, Sanika Karnik, and Maushmi S. Kumar

69

MC4R as a Target for Pharmacotherapeutic Treatment of Obesity and Type 2 Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . 935 Juliana Pereira Lopes Gonçalves, Daniel Palmer, and Morten Meldal

70

Nanotechnology: Can It Be a Crusader in Diabesity? . . . . . . . 947 Alexis Marie Speer and Mahua Choudhury

Part IX

Obesity Devices and Supplemental Material

71

Old and New Anti-obesity Devices for Medical, Surgical, and Endoscopical Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 959 Joel Faintuch and Salomao Faintuch

72

Electroceutical Approaches for Gastroparesis . . . . . . . . . . . . 967 Niranchan Paskaranandavadivel, Recep Avci, Nipuni Nagahawatte, Aydin Farajidavar, and Leo K. Cheng

73

Useful Online Resources Hosting Information on Obesity and Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 983 Joel Faintuch and Jacob J. Faintuch

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 989

Part I Epidemiology, Inheritance, Environment and Pathways

1

Introduction to Obesity and Diabetes: The Windows of Opportunity Joel Faintuch and Salomao Faintuch

Contents The Problem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 The Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Pediatric and Adult Obesity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Obesity-Induced Prediabetes or Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 State of the Art . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 The Three (or Five) Trillion Dollar Question . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Market Stratification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Ongoing Initiatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Final Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Abstract

Obesity and diabetes are not just associated with heart attack, stroke, kidney failure, shortened life span, and sudden death. They represent the three trillion question of the twentyfirst century. Indeed the combined world financial burden of obesity and diabetes already exceeds USD3 trillion, and could get 50%

J. Faintuch (*) Hospital das Clinicas, Sao Paulo University Medical School, Sao Paulo, Brazil e-mail: [email protected]; [email protected] S. Faintuch Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, USA

higher or more around 2030. No other disease category comes close. Healthcare budgets which are already strained could become overwhelmed worldwide. The purposes of this introduction and this book are not stern advices or scary threats. On the contrary, the aims are to present and discuss feasible, sensible, and up-to-date approaches for prevention, diagnosis, and handling of obesity and diabetes. Keywords

Weight loss · Metabolic diseases · Comorbidities · Financial cost · Obesogenic environment · Pediatric obesity · Recent onset diabetes · Recent onset obesity

# Springer Nature Switzerland AG 2020 J. Faintuch and S. Faintuch (eds.), Obesity and Diabetes, https://doi.org/10.1007/978-3-030-53370-0_1

3

4

J. Faintuch and S. Faintuch

The Problem

Pediatric and Adult Obesity

Type 2 diabetes (T2D) is the major cause of blindness, kidney failure, heart attack, and stroke. Obesity is currently the number one predisposing factor to T2D and is independently associated with cardiovascular and kidney disease, thus closing the circle. However, that is not all. Both shorten the life span, predispose to sudden death (Chen et al. 2019; Aune et al. 2018), and their clinical trajectory is rarely free from the mentioned comorbidities, along with myriads of others (Bray et al. 2018; Aga et al. 2019). Diabetics can suffer from as much as 97.5% prevalence of multimorbidity (Aga et al. 2019). Among the obese the metabolically healthy individual, exempt from associated illnesses, is a recognized category, however many suspects this status to be intrinsically unstable and short lived, eventually migrating to multimorbidity as well (Bray et al. 2018).

Children and adolescents are among the best candidates for obesity “cure.” Exaggerated adiposity is an unfavorable omen concerning adult life, however the prognosis is not necessarily ominous. Spontaneous normalization of body weight is still a possibility at these age brackets, particularly if a durable passion for sports and active life arises. Of course, structured dietary and lifestyle changes would be ideal, and the family should be actively engaged, not leaving the responsibility on the immature shoulders of the youngster (Ferraro and Adamo 2015). Stress- or lifestyle-induced, recent onset obesity in adults is also a comparatively fertile ground for successful interventions. As long as the precipitating factors can be neutralized, neverobese people who for a short while accumulated adipose tissue will rather easily revert to their previous, eutrophic condition. The expanded fat cell population will shrink, however, it is unlikely it will actually vanish. Adipocyte size, number, and metabolic status respond to lifestyle and pharmacologic interventions with tissue remodeling, sometimes quite remarkable, however the potential for weight regain survives. Consequently, lifelong surveillance and prevention measures will be advised (Moreira-Pais et al. 2020).

The Solution Weight loss ameliorates these diseases and most comorbidities in a dose-related manner—the more weight lost, the better the outcome (Bray et al. 2018). With a reductionist approach, one could affirm that this entire book is redundant and dispensable. Why worry about biomarkers, omics, and complex diagnostic and prognostic algorithms, if health can in many circumstances be restored just by shedding the unnecessary pounds of weight? Who should be interested in specialized and expensive teamwork, pharmacologic breakthroughs, or ingenious surgical and endoscopic interventions, if reconfiguring one’s diet will suffice? The fact is that both obesity and diabetes are “curable,” or at least amenable to prolonged, drug-free remission. Intensive lifestyle interventions can do the trick, along with bariatric and metabolic surgery (Ang 2018; Hirukawa et al. 2018; Willmer and Salzmann-Erikson 2018; Chen et al. 2018). What are the odds? And what does prolonged remission really mean?

Obesity-Induced Prediabetes or Diabetes There are reasons to believe that recent onset, obesity-related T2D in reasonably young people, much more than in the lean, the aged, and those with a diabetes history >5 years, is the most amenable to satisfactory remission, whether achieved by lifestyle (Ried-Larsen et al. 2019), drug (Hirukawa et al. 2018; Bohula et al. 2018) or surgical means (Hirukawa et al. 2018). Conversion of prediabetes to T2D is inhibited, new cases become more sparse, and even established disease can be fully compensated. How long will the honeymoon last?

1

Introduction to Obesity and Diabetes: The Windows of Opportunity

The longest available follow-ups are after bariatric surgery. The Swedish Obesity Study, which tracks a large cohort of adults submitted to a variety of operative techniques, has documented 38.1% and 30.4% remission after 10 and 15 years of follow up respectively (Sjostrom et al. 2014). Definition of prolonged remission is at variance with the recommendations of the American Diabetes Association, namely glycated hemoglobin HbA1c < 5.7% and fasting plasma glucose (FPG) < 100 mg/dL) without drugs for at least 5 years (Buse et al. 2009). In the alluded to the protocol, the adopted criterion was more lax, namely FPG < 110 mg/dL in the absence of antidiabetic treatment (Sjostrom et al. 2014). Discrepancies notwithstanding these results are respectable, not only because they robustly exceed those observed in the controls, but also because micro and macrovascular complications were similarly benefitted.

State of the Art The massive research efforts directed at obesity and diabetes in recent decades, confirmed what many had long suspected, namely that these diseases, in keeping with other metabolic aberrations, are preventable and potentially reversible, at least within certain limits. The requirements are early detection, removal of known drivers, and notably the implementation of a healthy and supervised lifestyle, with emphasis on diet, weight control, elimination of addictions, regular exercise, and combat of sedentarism.

The Three (or Five) Trillion Dollar Question For how long is that feasible with full compliance of the individuals, and how many would actually be touched by such policies? That is not the million-dollar question. It already involves over three trillion dollars, and in the coming decade could advance beyond five trillion, as outlined

5

below. During the last century, and especially a couple of decades after World War II, humanity has unwillingly cradled an obesogenic and hedonic environment, which started in industrialized countries and is spreading to all latitudes. What could be more gratifying than palatable food and drink on demand, especially because it is available, affordable, breaks no laws, and is not followed by a terrible hangover on the next day? Of course, the bathroom scale will protest, larger clothes will eventually be purchased, and sooner or later an appointment at a primary care facility will have to be scheduled. However, who cares about the future?

Market Stratification The global diabetes care drugs market reached USD69.7 billion in 2019 and is growing at a compound annual growth rate (CAGR) of 4.6% (www.mordorintelligence.com/industry-reports/ diabetes-drugs-market). The blood glucose monitoring systems market is smaller (USD10.1 billion in 2018), however it is expanding more rapidly (CAGR of 6.7%), thus the forecast for 2026 is USD17.1 billion (www.fortunebusinessinsights. com/industry-reports/blood-glucose-monitoringmarket-100648). The obesity prescription market is currently tiny, with few and not exceptionally effective agents. Only in 2026 is it expected to cross the billion-dollar barrier (www.bloomberg.com/ press-releases/2019-06-18/anti-obesity-prescrip tion-drugs-market-to-cross-us-1-000-million-by2026-says-tmr). In turn, the weight management market boasts a CAGR of 8.2% and will be worth a more hefty USD442 billion in 2026 (www. marketwatch.com/press-release/weight-manage ment-market-2019-size-statistics-growth-revenueanalysis-trends-industry-forecast-report%2D%2D 2025market-research-engine-2019-12-19). Wearable medical devices, an important share of which is devoted to obesity, diabetes, and weight management, was worth USD9 billion in 2018 and is growing at the exponential CAGR rate of 39% (www.gminsights.com/industry-

6

analysis/wearable-medical-devices-market). In one considers other lifestyle products and services, along with more specialized treatments such as bariatric operations and devices, the total market cap for these metabolic derangements could advance substantially beyond half-trillion dollars until 2025/2026. Calculations for the absolute global economic burden are more staggering. For diabetes, they are believed to increase from USD1.3 trillion in 2015, up to $2.5 trillion according to the past trends, by 2030. This translates as a share of global GDP from 1.8% in 2015 to a maximum of 2.2% (Bommer et al. 2018). Obesity weighs more, in all senses. Its 2014 global economic impact was USD2.0 trillion or 2.8% of the global gross domestic product (GDP). One should not be surprised if’s up to 50% more by 2030, given the current epidemiological trajectory. The only current combined burden of smoking (USD2.1 trillion) and alcohol addiction (1.4 trillion) is in the same range (Dobbs et al. 2014). No other disease category comes close. The industry forecast for inflammatory bowel disease drugs is in the range of USD22 billion for 2026 (www.grandviewresearch.com/press-release/globalinflammatory-bowel-disease-ibd-treatment), hepatitis C treatment is estimated at USD11 billion (2025) (www.worldhepatitisalliance.org/news/sep-2015/ cost-comprehensive-global-viral-hepatitis-preven tion-and-treatment-effort-might-peak/), and the oncology drug market should not exceed a comparatively negligible USD176.5 million (2025) (www.alliedmarketresearch.com/oncology-can cer-drugs-market). Devices, palliative assistance, and ancillary care, along with indirect costs (absenteeism, premature death) could tip the scales a lot further, however still far away from the figures mentioned above.

Ongoing Initiatives Of course academic and government healthcare planners and scientists are not staying idle. Major local or nationwide diabetes and obesity initiatives are going on in the USA, the UK, Australia, Canada, New Zealand, Austria, India,

J. Faintuch and S. Faintuch

China, Israel, and United Arab Emirates, among others. From taxes and legislation inhibiting intake of risky foods and drinks, not overlooking planned cities and buildings that stimulate walking and stair climbing, to targeted anti-obesity and antidiabetic lifestyle and pharmacological interventions, policy makers have their hands full (Galaviz et al. 2018). What are the prospects for a “magic pill” in the obesity and type 2 diabetes context? Even though the industry is putting out safer and more powerful drugs nearly every year, and invasive as well as intensive lifestyle interventions improve, prolonged remission is still not within the grasp of the masses, only of limited groups (Ang 2018; Hirukawa et al. 2018; Willmer and SalzmannErikson 2018; Chen et al. 2018; Ferraro and Adamo 2015). Incidentally, there is much hope also for candidates with type 1 diabetes, as stem cell therapy and immunotherapy are making large strides (https://labiotech.eu/features/immunother apy-type-1-diabetes. Breakthrough type 1 diabetes).

Final Considerations In the first chapter of The Descent of Man, and Selection in Relation to Sex, published in 1871, Charles Darwin argued that some anatomical structures were useless, and would eventually disappear. These included toes, wisdom teeth, paranasal sinuses, cervical ribs, and even body hair (Darwin 1981). He was not the only one to engage in phenotypic futures studies. In more recent century, specifically in 1993, Nebel and Wright predicted that man will eventually increase brain capacity, and undergo leg atrophy (Nebel and Wright 1993). Indeed the more gray and white matter, the better to deal with sophisticated computers and to analyze big datasets. On the other hand, who needs to carry around long and heavily muscled legs if elevators, escalators, cars, and other conveyances are ubiquitous? Both prophecies failed to include obesity and diabetes. Men and women are becoming smarter, communicating instantly, and moving around at increasing speed, however they are paying dearly

1

Introduction to Obesity and Diabetes: The Windows of Opportunity

in the form of metabolic illnesses. If one does not intend to pass on these scourges to the coming generations, one has to act here and now. This book represents an effort by highly regarded specialists and respected scholars from different continents, to present new ways and means not only to identify and manage obesity and diabetes, but also to prevent it before it moves out of control.

References Aga F, Dunbar SB, Kebede T, Gary RA (2019) The role of concordant and discordant comorbidities on performance of self-care behaviors in adults with type 2 diabetes: a systematic review. Diabetes Metab Syndr Obes 12:333–356 Ang GY (2018) Reversibility of diabetes mellitus: narrative review of the evidence. World J Diabetes 9 (7):127–131 Aune D, Schlesinger S, Norat T, Riboli E (2018) Diabetes mellitus and the risk of sudden cardiac death: a systematic review and meta-analysis of prospective studies. Nutr Metab Cardiovasc Dis 28(6):543–556 Bohula EA, Scirica BM, Inzucchi SE, DK MG, Keech AC, Smith SR, Kanevsky E, Murphy SA, Leiter LA, Dwyer JP, Corbalan R, Hamm C, Kaplan L, Nicolau JC, Ophuis TO, Ray KK, Ruda M, Spinar J, Patel T, Miao W, Perdomo C, Francis B, Dhadda S, Bonaca MP, Ruff CT, Sabatine MS, Wiviott SD, CAMELLIATIMI 61 Steering Committee Investigators (2018) Effect of lorcaserin on prevention and remission of type 2 diabetes in overweight and obese patients (CAMELLIA-TIMI 61): a randomised, placebocontrolled trial. Lancet 392(10161):2269–2279 Bommer C, Sagalova V, Heesemann E, Manne-Goehler J, Atun R, Bärnighausen T, Davies J, Vollmer S (2018) Global economic burden of diabetes in adults: projections from 2015 to 2030. Diabetes Care 41 (5):963–970 Bray GA, Heisel WE, Afshin A, Jensen MD, Dietz WH, Long M, Kushner RF, Daniels SR, Wadden TA, Tsai AG, Hu FB, Jakicic JM, Ryan DH, Wolfe BM, Inge TH (2018) The science of obesity management: an endocrine society scientific statement. Endocr Rev 39 (2):79–132 Buse JB, Caprio S, Cefalu WT, Ceriello A, Del Prato S, Inzucchi SE, McLaughlin S, Phillips GL, Robertson RP, Rubino F, Kahn R, Kirkman MS (2009) How do we define cure of diabetes? Diabetes Care 32 (11):2133–2135 Chen JC, Hsu NY, Lee WJ, Chen SC, Ser KH, Lee YC (2018) Prediction of type 2 diabetes remission after metabolic surgery: a comparison of the individualized

7

metabolic surgery score and the ABCD score. Surg Obes Relat Dis 14(5):640–645 Chen H, Deng Y, Li S (2019) Relation of body mass index categories with risk of sudden cardiac death. Int Heart J 60(3):624–630 Darwin C (1981) The descent of man and selection in relation to sex. Princeton Science Library, Princeton, NJ Dobbs R, Sawers C, Thompson F, Manyika J, Woetzel JR, Child P, McKenna S, Spatharou A (2014) Overcoming obesity: an initial economic analysis. McKinsey Global Institute, Jakarta, ID. www.mckinsey.com/ mgi/our-research/discussion-papers-and-briefings. Accessed 24 Mar 2020 Ferraro ZM, Adamo KB (2015) Maternal, paternal, and societal efforts are needed to “cure” childhood obesity. Mayo Clin Proc 90(4):555 Galaviz KI, Venkat Narayan KM, Lobelo F, Weber MB (2018) Lifestyle and the prevention of type 2 diabetes: a status report. Am J Lifestyle Med 12(1):4–20 Hirukawa H, Hashiramoto M, Tanizawa Y, Kaku K (2018) Pioglitazone and sulfonylurea remission from type 2 diabetes mellitus and antiatherosclerosis in Japan (PREVENT-J) study group. Remission of hyperglycemia after withdrawal of oral antidiabetic drugs in Japanese patients with earlystage type 2 diabetes. J Diabetes Investig 9 (5):1119–1127 https://labiotech.eu/features/immunotherapy-type-1-diabe tes/. Breakthrough type 1 diabetes Moreira-Pais A, Ferreira R, Neves JS, Vitorino R, Moreira-Gonçalves D, Nogueira-Ferreira R (2020) Sex differences on adipose tissue remodeling: from molecular mechanisms to therapeutic interventions. J Mol Med (Berl) 98(4):483–493 Nebel BJ, Wright RT (1993) Environmental science: the way the world works 1993. Available at https:// thepopculturecompany.com. Accessed 30 Mar 2020 Ried-Larsen M, Johansen MY, MacDonald CS, Hansen KB, Christensen R, Wedell-Neergaard AS, Pilmark NS, Langberg H, Vaag AA, Pedersen BK, Karstoft K (2019) Type 2 diabetes remission 1 year after an intensive lifestyle intervention: a secondary analysis of a randomized clinical trial. Diabetes Obes Metab 21 (10):2257–2266 Sjostrom L, Peltonen M, Jacobson P, Ahlin S, AnderssonAssarsson J, Anveden A, Bouchard C, Carlsson B, Karason K, Lonroth H, Naslund I, Sjostrom E, Taube M, Wedel H, Svensson PA, Sjoholm K, Carlsson LM (2014) Association of bariatric surgery with long-term remission of type 2 diabetes and with microvascular and macrovascular complications. JAMA 311:2297–2304 Willmer M, Salzmann-Erikson M (2018) The only chance of a normal weight life: a qualitative analysis of online forum discussions about bariatric surgery. PLoS One 13(10):e0206066 www.alliedmarketresearch.com/oncology-cancer-drugsmarket. Accessed 30 Mar 2020

8 www.bloomberg.com/press-releases/2019-06-18/anti-obe sity-prescription-drugs-market-to-cross-us-1-000-mil lion-by-2026-says-tmr. Accessed 30 Mar 2020 www.fortunebusinessinsights.com/industry-reports/ blood-glucose-monitoring-market-100648. Accessed 30 Mar 2020 www.gminsights.com/industry-analysis/wearable-medi cal-devices-market. Accessed 30 Mar 2020 www.grandviewresearch.com/press-release/global-inflam matory-bowel-disease-ibd-treatment. Accessed 30 Mar 2020

J. Faintuch and S. Faintuch www.marketwatch.com/press-release/weight-manage ment-market-2019-size-statistics-growth-revenue-anal ysis-trends-industry-forecast-report%2D%2D2025mar ket-research-engine-2019-12-19. Accessed 30 Mar 2020 www.mordorintelligence.com/industry-reports/diabetesdrugs-market. Accessed 30 Mar 2020 www.worldhepatitisalliance.org/news/sep-2015/cost-com prehensive-global-viral-hepatitis-prevention-and-treat ment-effort-might-peak/. Accessed 30 Mar 2020

2

Nutrition Transition and Obesity Trends in Argentina Within the Latin American Context Sonia Alejandra Pou, Natalia Tumas, and Laura Rosana Aballay

Contents Understanding the Path to the Obesity Epidemic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 The Population Context . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Worldwide Changes in Recent Decades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 The Burden of Obesity Worldwide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Dietary Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Findings in Latin America . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Focus on Argentina . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Highly Processed Foods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Physical Activity Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Disease Burden . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12 13 13 13 14 14 14

Public Health Interventions and Future Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Childhood Undernutrition and Adult Obesity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Abstract

The world population has undergone a rapid shift in dietary and physical activity patterns, from traditional diets to a dietary pattern characterized by highly processed foods and

sugar-sweetened beverages, coupled with increasingly sedentary lifestyles. These shifts have been concomitant with demographic, macroeconomic, and technological changes, and closely related to the widespread obesity

S. A. Pou (*) Faculty of Medical Sciences, Institute for Investigations in Health Sciences (INICSA), National University of Cordoba, National Council for Scientific and Technical Investigations (CONICET), Cordoba, Argentina

N. Tumas Center for Investigations and Studies on Culture and Society (CIECS), National Council for Scientific and Technical Investigations (CONICET), National University of Cordoba, Cordoba, Argentina

Faculty of Medical Sciences, Statistics and Biostatistics, School of Nutrition, National University of Cordoba, Cordoba, Argentina e-mail: [email protected]

Faculty of Health Sciences, School of Nutrition, Catholic University of Cordoba, Cordoba, Argentina L. R. Aballay Faculty of Medical Sciences, Statistics, Biostatistics and Informatics Applied to Nutrition, School of Nutrition, National University of Cordoba, Cordoba, Argentina

# Springer Nature Switzerland AG 2020 J. Faintuch and S. Faintuch (eds.), Obesity and Diabetes, https://doi.org/10.1007/978-3-030-53370-0_2

9

10

S. A. Pou et al.

epidemic. Barry Popkin (University of North Carolina at Chapel Hill, USA) has defined the entire process as Nutrition Transition and has written extensively about its stages, drivers, and consequences. Based on this literature and on our previous work, in this chapter we present the key elements of the nutrition transition process in developing countries, describing its distinctive features in the Latin America region, especially in Argentina. We also describe obesity trends in this context. Finally, we discuss public health interventions in the developing world, and future perspectives to deal with a still unresolved consequence of the nutrition transition, the obesity and noncommunicable diseases epidemic. Keywords

Obesity burden · Obesity epidemic · Obesity trends · Obesity public health · Highly processed foods · Nutrition transition

Understanding the Path to the Obesity Epidemic The nutrition transition theory describes the process of shifts in the diet and in the physical activity patterns that result in changes in stature, body composition and body size of populations (Popkin 1994, 2004). Both quantitative and qualitative dimensions are involved in these changes (Popkin 2002a, 2009). Several societies seem to converge on a shift away from traditional diets toward a more globalized pattern characterized by less legumes, vegetables, and fruits, and more animal-source foods, edible oils, and processed foods—high in refined carbohydrates, added sugars, and sweeteners (Popkin 2002a, 2015, 2017; United Nations System, Standing Committee on Nutrition 2010). Physical activity decreases rapidly, driven by more sedentary jobs and leisure activities, and the increasing use of vehicles (Popkin 2006, 2015). In regard to the nutritional status, a shift from increased prevalence of

undernutrition toward a high prevalence of overweight and obesity is observed (Popkin 1994, 2004).

The Population Context Two historic processes affect and are affected by nutritional transition: the demographic transition and the epidemiologic transition (Popkin 2002a). The demographic transition is defined as the shift from a population pattern of high fertility and high mortality, to another of low fertility and low mortality, with the consequent life expectancy increase (Notestein 1945). Closely related to these demographic changes is the epidemiological transition, which refers to the evolution from a pattern of high prevalence of infectious diseases, to predominance of noncommunicable diseases (NCDs) (Omran 1971). These transitions have some elements in common: they describe the changes observed in the demographic, health and diet dynamics of the populations (mainly in developed countries) through a succession of stages; they share common pathways; they consider that the stages (with more or less delay) will occur in all regions worldwide; and they were designed with the purpose of making forecasts and planning new socioeconomic, food, and health policies (Popkin et al. 2012; Nicolau-Nos and Pujol-Andreu 2011). The interplay among these epidemiologic, demographic, and social changes is such, that it determines the nature and pace of nutritional shifts (Popkin 2001). Five broad nutrition patterns were proposed by the lead author of this theory, Barry Popkin (Popkin 1993, 2002a), to describe the nutrition transition. Although the patterns were outlined as historical stages, they are not restricted to the periods in which they first arose. In point of fact, some nutrition transition patterns coexist at the same time, with spatial and socioeconomic variations. We summarize these broad nutrition transition patterns in Table 2.1. The shifts involved in these patterns occur in different regions at different rates; however, there is a consensus regarding that the most rapid

2

Nutrition Transition and Obesity Trends in Argentina Within the Latin American Context

11

Table 2.1 Summary of the nutrition transition patterns according to the dimensions involved Nutrition transition pattern Collecting food

Famine

Receding famine

Nutrition-related noncommunicable diseases

Behavioral change

Diet Varied diet, high in carbohydrates and fiber, and low in saturated fat Less varied diet, cereals predominant. Periods of food scarcity Less starchy staples and more fruit, vegetables and animal protein intake. Lower variety of diet and famines Higher in fat (specially saturated), cholesterol, refined carbohydrates and processed foods. Lower in fiber and polyunsaturated fatty acids More carbohydrates, fruits and vegetables; less fat and processed food

Physical activity High level of physical activity Little modification in physical activity levels Physical activity levels started to decrease

Nutritional status Robust, lean, low malnutrition prevalence Nutritional deficiencies, stature reduction Several nutritional deficiencies disappear, stature grows

Increasing sedentary jobs and lifestyles

Obesity prevalence increases, many disabling conditions

High leisure exercises, sedentary jobs

Lower body-fat and obesity; better bone health

Other features Typical of hunter– gatherer Agriculture, livestock farming Deepening of social stratification Crop rotation, fertilizer use, industrial revolution. Women join the labor force Technology revolution. Characteristics of highincome societies and increasing low-income societies Service sector mechanization. Changes aimed to increase the disabilityfree life expectancy

Data from Popkin (1993), (2001) (2002a), and (2004)

change is observed in developing countries (Popkin 2009; Hawkes et al. 2017). Specifically, the shifts in diet and physical activity patterns seem to be particularly accelerated in the lowand middle-income countries (LMICs) (Popkin et al. 2012; Popkin 2002b). It is worth mentioning that Popkin has written extensively about the influence of changes in the food system and macroeconomic factors, that underlie many of these worldwide dietary shifts (Popkin 2009, 2017; Popkin et al. 2012), remarking that the major influence on the obesity epidemic must be viewed as environmental rather than personal or genetic (Popkin 2001). In line with this assumption, other authors state that along with income, relative food prices and preferences are a major determinant of dietary patterns (Finaret and Masters 2019), and therefore of the obesity outcome.

Worldwide Changes in Recent Decades Four interrelated macroeconomic and technological factors have been pointed out. A critical driver

is the technology that affects economic and domestic works, the production and processing of foods, and the expansion of mass marketing, which leads to changes in dietary patterns and related health conditions. Additionally, transportation facilities (e.g., trains) and leisure sedentarypromoting devices (e.g., television, mobile phones, and computers) had a central impact on the reduction of physical activity levels (Popkin 2006, 2015). Another widely studied driver is urbanization. This demographic process is associated with a greater variety and availability of food, more marketing activities on foods, higher food processing, and increased intake of food away from home (Since jobs are more frequently incompatible with home food preparation). The urbanization process has experienced an enormous acceleration, and nowadays approximately 55% of the world’s population is urban (United Nations 2017). The Latin American and Caribbean region are the most urbanized in the world (about 80% rate), and in Argentina, around 91% of the population live in urban areas (Pou et al. 2017).

12

More robust per capita income and expansion of global trade are great drivers of the nutrition transition process. While income has increased worldwide, the prices of many foods have diminished, thus leading to lower proportions of income allocated to food. Besides, income increase allows acquiring labor-saving devices and others that foster a sedentary lifestyle (Popkin 2015). The opening of global trade in goods and services provides more opportunities to access modern media, food retail, food services, and technologies that reduce physical activity (Popkin 2006, 2015). A recent analysis about trade openness and the obesity epidemic that included 175 countries during the 1975–2016 period, concluded that trade openness was positively associated with country obesity prevalence, and its influence concentrated among developing nations (An et al. 2019). Despite the general tendencies, wide inequalities remain in many LMIC countries, where undernutrition (underweight, stunting, micronutrient deficiencies) persists and coexists with increased prevalence of overweight, obesity, and associated NCDs (United Nations System, Standing Committee on Nutrition 2010; Popkin et al. 2012; Ng et al. 2014). This is the so-called “double burden of malnutrition,” which can be observed at the country, community, household, and even at the individual levels (United Nations System, Standing Committee on Nutrition 2010; Popkin et al. 2012). This complex nutritional and epidemiological scenario constitutes an enormous challenge for the public health of these countries, and particularly for the Latin American region, as described in detail below.

The Burden of Obesity Worldwide Most of the world’s population lives in countries where overweight and obesity kill more people than underweight, and it is estimated that at least 2.8 million people die each year as a consequence of overweight or obesity (World Health Organization 2017, 2018a), even though these nutritional conditions are preventable.

S. A. Pou et al.

In the Americas, in 2016 the prevalence of overweight and obesity in adults was 66.2% and 59.3% in men and women, respectively. Among the countries with the highest prevalence are the USA (68%), Mexico (65%), Canada, and Bahamas (64%) (Organización Panamericana de la Salud 2019). In Latin America and the Caribbean, it has been noted that 7.5% of children under 5 years of age live with overweight, whereas worldwide prevalence is 5.9% (FAO, OPS, WFP, UNICEF 2019). Obesity is not only a disease, but also a metabolic risk factor associated with other NCDs such as cardiovascular problems, diabetes, and cancer (Finucane et al. 2011; Ford et al. 2017), which are the main causes of death and disability worldwide. The World Health Organization (WHO) reported that 71% of the global disease burden is due to NCDs and that these diseases disproportionately affect people in LMICs (World Health Organization 2018b). In Argentina, NCDs were responsible for the largest proportion of deaths in 2016 (almost 80% of total mortality) (World Health Organization 2018c). Based on the last National Survey of Risk Factors, it was estimated that 61.6% of the adult population living in urban areas of Argentina in 2018 have overweight and among them, 25.4% present obesity. This level of prevalence is similar to developed countries and represents a growth of almost double in 13 years (from an obesity prevalence of 14.6% in 2005) (Ministerio de Salud y Desarrollo Social de la Nación 2019). According to the World School Health Survey (Ministerio de Salud y Desarrollo Social de la Nación 2018), the prevalence of overweight and obesity in students aged between 13 and 17 in Argentina was 30.3% and 7.4%, respectively, with higher values in men than in women. Excess weight in the specific group of adolescents (aged 13–15 years old) has increased progressively throughout the three editions of the World School Health Survey; the overweight prevalence increased from 24.5% (2007) to 28.6% (2012) and 33.1% (2018) and the percentage of students with obesity was about 4.4% in 2007, with values to 5.9% and 7.8% in 2012 and 2018, respectively

2

Nutrition Transition and Obesity Trends in Argentina Within the Latin American Context

13

(Ministerio de Salud y Desarrollo Social de la Nación 2018).

recommendations, respectively, in most of the countries (Kovalskys et al. 2019).

General Dietary Patterns

Focus on Argentina

The dietary pattern descriptions are based on extensive research carried out in higher-income countries, while the scientific evidence is comparatively scarce in LMICs. Yet Popkin (2015) sheds light on this matter and points out that, nowadays, there is sufficient data available about LMICs to document this generalized dietary trend in all urban areas and, increasingly, in rural ones: (1) a huge increase in the consumption of vegetable oils and the practice of frying food, instead of using traditional healthier cooking methods; (2) very high levels of sugar-sweetened beverages and fruit juice intakes; (3) increased consumption of animal-source foods; (4) a diet shift toward the intake of highly processed food products and a reduction of legumes, fruits, and vegetables; (5) away-from-home meals, frequent snacking and a rise in eating frequency (Popkin 2009, 2011, 2015).

According to the ELANS (Kovalskys et al. 2019), Argentina was the leading consumer of sugarsweetened beverages (mean of 1245 g/day) and red meat (prevalence of consumption of 82.3%, average consumption of 129.7 g/day), during 2014–2015. Particularly in Argentina and Chile, processed meat consumption was more common among low socioeconomic groups. Inversely, Argentina is among the countries with less legumes consumption in the region. Regarding fruits and vegetables mean intakes were markedly below current recommendations (at least five servings/day), as in all the countries of the region. This is consistent with the results of the last National Surveys of Risk Factors that reported a mean intake of only two servings/day of these vegetable -source foods in the Argentinian adult population in 2018 (Ministerio de Salud y Desarrollo Social de la Nación 2019). Nevertheless, both fruits and vegetables were consumed in greater amounts among the low socioeconomic groups in most of the Latin American countries, including Argentina (Kovalskys et al. 2019). In the 1996–2013 National Survey of Household Expenditure (Zapata et al. 2016; Zapata and Rovirosa 2016), the traditional diet of the Argentinian people in the past (mainly unprocessed or minimally processed foods) is now moving to a diet rich in processed foods. Similar to the ELANS results, but from a dynamic perspective, the authors highlight the higher and increased apparent consumption of sugarsweetened soft drinks or juices and processed meats (This consumption has doubled and tripled, respectively, in the last 20 years). Moreover, total fruit consumption decreased by 41% in the study period. Yet when income increases, consumption and fruit diversity improve as well. The consumption of ready-to-eat foods also grows as household income becomes more elevated (Zapata et al. 2016; Zapata and Rovirosa 2016).

Findings in Latin America Although these trends are widespread even in Latin American countries, there is much heterogeneity between and within countries (by age, gender, and sociodemographic conditions) (Popkin 2002a; Kovalskys et al. 2019). A multicenter cross-sectional study assessing food consumption in adults (15–65 years old) in an urban sample from 8 Latin American countries (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Peru, and Venezuela), called ELANS (Latin American Study of Nutrition and Health) (Kovalskys et al. 2019), indicates in general, deficiencies for nutrient-dense food groups; healthy food tends to be more consumed by high socioeconomic persons and older people; vegetables and red meat remain the two most consumed food groups in the region, although their amounts are below and over

14

Highly Processed Foods Processed food products have been defined as “substances extracted and refined from unprocessed or minimally processed foods that are ‘ready-to-eat’ or ‘ready-to-heat,’ made from industrially prepared ingredients and additives, usually highly palatable and intensively marketed, and often high in free sugars, transfats and low in micronutrients” (Sievert et al. 2019). Although the health costs or benefits of food processing are still discussed, a report of the Pan American Health Organization on this matter discourages their consumption; it also indicates that sales of ultra-processed food products (also called highly processed food products) are associated with weight gain and obesity in Latin America (PAHO-OMS 2015). It was estimated that the volume sales of ultra-processed drinks per capita is about 184.5 kg/capita/year in Argentina, which ranks among the highest values, along with the USA (238.8 kg/capita/year) and Mexico (188.5 kg/capita/year) (Vandevijvere et al. 2019). Regarding food selection among Argentinian adolescents, a tendency to low consumption of fruits and vegetables was observed from the World School Health Survey 2018 (Ministerio de Salud y Desarrollo Social de la Nación 2018). Only 21% and 10.5% of them consumed fruits and vegetables, respectively, two or more times per day. A public health issue that needs to be considered is that approximately 10% of those adolescents currently eat fast food 3 or more days a week away from home, around 50% more than in 2012 when only 6.8% of the total of number of participants aged between 13–15 years old adopted this dietary practice. Moreover, a third of the adolescents declared a consumption of sugar-sweetened drinks of 1 or more times a day.

Physical Activity Patterns A sedentary lifestyle or low level of physical activity is an indicator of low energy expenditure and constitutes one of the main modifiable risk factors of most NCDs (World Health

S. A. Pou et al.

Organization 2018b). Some researchers argue that physical inactivity or sedentary lifestyle is the fourth-ranking risk factor for global mortality (6% of deaths recorded worldwide) (Guthold et al. 2018). The results of the National Surveys of Risk Factors show that people from this country have a low level of physical activity, increasing its prevalence from 54.7% in 2013 to 65% in 2018 (Ministerio de Salud y Desarrollo Social de la Nación 2019). The World School Health Survey confirmed that only 16.5% of students aged between 13 and 17 were physically active in 2018, and 55.3% of them spent at least 3 h a day sitting, outside school hours. This is a clear indicator of sedentary behavior in this population. Meanwhile, the percentages of physical inactivity among young people remain high, mainly among women (Ministerio de Salud y Desarrollo Social de la Nación 2018).

Disease Burden Latin America, along with the Middle East and North Africa, is one of the low- and middleincome regions with the highest burden of obesity (Popkin and Reardon 2018). Changes in diet and activity patterns lead to the emergence of chronic disease problems and increased disability (Popkin and Gordon-Larsen 2004; Popkin et al. 1996). In Latin America (Popkin 2002a), many countries entered into the so-called nutrition related-NCDs stage far earlier than others. Haiti and some Central American subpopulations, in 2002 were still in the receding famine stage. In contrast, Mexico experienced an accelerated transition in the 1990s (Popkin 2002a). While obesity prevalence continued to increase among all socioeconomic groups, the highest burden was among disadvantaged women (Pérez-Ferrer et al. 2018). Argentina, an upper-middle income country, with a current total population that exceeds 40 million people (40,117,096, census 2010) is ranked as the fifth most populous country in this region. The nutrition transition process presents geographical differences within this country. In

2

Nutrition Transition and Obesity Trends in Argentina Within the Latin American Context

15

Table 2.2 Summary of the nutrition transition profiles in Argentina (2005–2013) according to the dimensions involved

Nutrition transition profiles Socionutritional lag

Double burden of malnutrition

Incipient socionutritional improvement

Nutritional features High prevalence of stunting in children; low prevalence of childhood obesity

High prevalence of childhood and adult obesity; intermediate prevalence of stunting in children Low prevalence of stunting in children and adult obesity

Sociodemographic characteristics High proportion of poverty households and population without health insurance; low proportion of population with higher education; relatively high infant mortality rates. High proportion of urban households

Low proportion of poverty households

Provinces in cluster Misiones, Corrientes, Tucumán, Santiago del Estero, Jujuy, Formosa, Río Negro, San Juan, Chaco, Salta

Catamarca, La Rioja, Santa Fe, Buenos Aires, Neuquén, Chubut, Santa Cruz, Tierra del Fuego Córdoba, San Luis, Mendoza, La Pampa, Autonomous City of Buenos Aires, Entre Ríos

Related patterns of nutrition transition theory Receding famine

Moving from “receding famine” to “degenerative diseases” stage Behavioral change

Data from Tumas et al. (2019)

our recent work (Tumas et al. 2019), we identified three profiles, which were named “socionutritional lag” (characterized by undernutrition and socioeconomically disadvantaged conditions), “double burden of malnutrition” (undernutrition by stunting and overweight in highly urbanized scenarios), and “Incipient socionutritional improvement” (low prevalence of malnutrition and more favorable poverty indicator values). These profiles allowed us to differentiate the Argentinian provinces into three groups according to the nutritional status and sociodemographic characteristics of their populations. The key issues in each of the profiles identified are summarized in Table 2.2. As discussed by Tumas et al. (2019), the “socionutritional lag” profile is closely related to the so-called “receding famine” pattern proposed in the NT theory, given that child undernutrition problems are distinctive characteristics in both scenarios. The “double burden of malnutrition,” in turn, could reflect a transitional situation of these populations between the “receding famine” and the “degenerative diseases” stage stated by Popkin, which is also a distinctive characteristic of many developing regions. On the other hand, the “incipient socionutritional improvement”

profile could be linked to the last stage of the nutrition transition, the “behavioral change” pattern, because the low prevalence of malnutrition (both under- and over-nutrition), together with favorable socioeconomic conditions were the most dominant features. Interestingly, this was the only profile that showed no associations with the obesity burden in Argentina. These results highlight the important role of sociodemographic factors such as urbanization and poverty levels in shaping nutrition transition profiles in Argentina (Tumas et al. 2019). Previous studies focused on the link between specific dietary patterns and obesity or NCDs in urban populations of Argentina already found an association between unhealthy dietary patterns with obesity (Pou et al. 2016), as well as with several diet-related cancers (Niclis et al. 2015; Pou et al. 2012, 2014a, b; Tumas et al. 2014).

Public Health Interventions and Future Perspectives In response to the growing burden of NCDs, the global community has worked through the World Health Organization and the United Nations,

16

aiming to reduce premature mortality from NCDs by 25% until 2025 (World Health Organization 2018b). However, the results of the global consensus and derived interventions have not been successful. As Popkin anticipated, achieving the pattern of behavioral change (Popkin 2009), seems to be quite difficult in the current scenario of the Latin American region. The accelerated speed at which nutritional and epidemiological changes occur in developing countries often exceeds the national capacity of these countries to address the rapid increase of NCDs and to engender a healthy transition (Popkin 2002b; Lancet 2017). In addition, the rapidly increasing burden of overweight and obesity coupled with increased waist circumferences and major diet shifts, adversely affect the burden of diabetes and other metabolic disorders (Popkin 2015), which are capital public health problems in the developing world. In LMICs, it is also noticeable that the double burden of malnutrition underlies a context of food insecurity coupled with energy imbalance (Popkin 2002b); this may reflect persistent social inequalities in health distribution that should be addressed.

Childhood Undernutrition and Adult Obesity Current hypotheses of the developmental origins of adult disease merit special attention in these regions, where obesogenic environments are expanding while undernutrition persists (Popkin et al. 2012; Wells et al. 2020). According to Wells et al. (2020), early undernutrition in life (during fetal and infant development) followed by later energy imbalance, impose a high metabolic load on a depleted capacity for homeostasis; this may exacerbate the health costs of adult obesity especially among individuals who have previously suffered from undernutrition. Public health policy interventions and programs should simultaneously address malnutrition caused by energy imbalance linked to nutritional deficiencies (i.e., stunting, anemia, and other nutritional

S. A. Pou et al.

deficiencies), along with an excess of body weight (i.e., overweight or obesity). These need to focus on the early stages of life and to adopt a life-course perspective. Tirado et al. (2016) found that all 18 countries Latin American countries under study had relevant policies to address malnutrition, especially undernutrition, and micronutrient deficiencies, but only some of them had policies to address overweight and obesity (Tirado et al. 2016). Especially in LMICs, it has been highlighted the central role of breastfeeding (Wells et al. 2020). This practice, economically affordable for the population living in poverty, increases the chances of achieving a healthy weight and growth during early childhood. Ongoing initiatives include taxation of sugar-sweetened beverages, marketing control especially concerning child-oriented, front-ofpackage labeling profiles with a positive or negative logo, and special regulations related to schools and/or other public facilities (Popkin 2017). Tirado et al. (2016) report that regulatory frameworks to address overweight and obesity have been introduced. However, the authors highlight the scarcity of data on the allocation of human and financial resources to promote balanced nutrition (a crucial element in terms of the efficacy of public policies), and that most of the countries studied had food-based dietary guidelines, but lacked the legislation to increase access to healthy food and/or address the obesogenic environment (Tirado et al. 2016). We want to emphasize the relevance of timely feedbacks on current policies. Besides, we highlight the need to improve systems and instruments for data collection on nutrition and diet in developing countries, especially from Latin America. In this regard, Walls et al. (2018) reported that the standardized instruments commonly used to assess diets in LMICs are not appropriate for measuring, for example, the consumption of ultra-processed foods (2018). In accordance with Popkin, we believe that in order to tackle obesity and NCDs epidemics, we must focus our major efforts on finding “environmental solutions” (Popkin 1998). Individual-level interventions conceived from a biomedical approach, are too

2

Nutrition Transition and Obesity Trends in Argentina Within the Latin American Context

simplistic for addressing these complex and multifactorial diseases. An intersectoral approach is essential for the definition and implementation of public policies; this means involve multiple actors, including in the first place the food and beverage industries as well as government officials.

References An R, Guan C, Liu J, Chen N, Clarke C (2019) Trade openness and the obesity epidemic: a cross-national study of 175 countries during 1975–2016. Ann Epidemiol 37:31–36. https://doi.org/10.1016/j. annepidem.2019.07.002 FAO, OPS, WFP, UNICEF (2019) Panorama de la seguridad alimentaria y nutricional en América Latina y el Caribe 2019. FAO, Santiago, 135 p Finaret AB, Masters WA (2019) Beyond calories: The new economics of nutrition. Ann Rev Resour Econ 11:237–259. https://doi.org/10.1146/annurevresource-100518-094053 Finucane MM, Stevens GA, Cowan MJ et al (2011) National, regional, and global trends in body-mass index since 1980: systematic analysis of health examination surveys and epidemiological studies with 960 country-years and 9•1 million participants. Lancet 377(9765):557–567. https://doi.org/10.1016/S01406736(10)62037-5 Ford ND, Patel SA, Narayan KM (2017) Obesity in lowand middle-income countries: burden, drivers, and emerging challenges. Annu Rev Public Health 38:145–164. https://doi.org/10.1146/annurevpublhealth-031816-044604 Guthold R, Stevens GA, Riley LM, Bull FC (2018) Worldwide trends in insufficient physical activity from 2001 to 2016: a pooled analysis of 358 population-based surveys with 1
9 million participants. Lancet Glob Health 6(10):e1077–e1086. https://doi.org/10.1016/ S2214-109X(18)30357-7 Hawkes C, Harris J, Gillespie S (2017) Urbanization and the nutrition transition. In: Global food policy report, vol 4. IFPRI, Washington, DC, pp 34–41 Kovalskys I, Rigotti A, Koletzko B et al (2019) Latin American consumption of major food groups: Results from the ELANS study. PLoS One 14(12):e0225101. https://doi.org/10.1371/journal.pone.0225101 Ministerio de Salud y Desarrollo Social de la Nación (2018) Encuesta Mundial de Salud Escolar. Argentina 2018. Resumen ejecutivo total nacional. CABA: Secretaría de Gobierno de Salud, 13 p Ministerio de Salud y Desarrollo Social de la Nación (2019) 4ta Encuesta Nacional de Factores de Riesgo. Informe definitivo. Buenos Aires: Dirección Nacional de Promoción de la Salud y Control de Enfermedades Crónicas No Transmisibles, 262 p

17

NCD Risk Factor Collaboration (NCD-RisC) (2017) Worldwide trends in body-mass index, underweight, overweight, and obesity from 1975 to 2016: a pooled analysis of 2416 population-based measurement studies in 128
9 million children, adolescents, and adults. Lancet 390(10113):2627–2642. https://doi.org/10. 1016/S0140-6736(17)32129-3 Ng M, Fleming T, Robinson M et al (2014) Global, regional, and national prevalence of overweight and obesity in children and adults during 1980–2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet 384:766–781. https://doi.org/10. 1016/S0140-6736(14)60460-8 Niclis C, Román MD, Osella AR, Eynard AR, Díaz MP (2015) Traditional dietary pattern increases risk of prostate cancer in Argentina: results of a multilevel modeling and bias analysis from a case-control study. J Cancer Epidemiol Rev 2015:179562. https://doi.org/ 10.1155/2015/179562 Nicolau-Nos R, Pujol-Andreu J (2011) Aspectos políticos y científicos del modelo de la transición nutricional: evaluación crítica y nuevos desarrollos. Documentos del Trabajo de la Sociedad española de Historia Agraria, pp 11–15 Notestein F (1945) Population: the long view. In: Schultz TW (ed) Food for the world. University of Chicago Press, Chicago, IL, pp 36–57 Omran AR (1971) The epidemiologic transition. A theory of the epidemiology of population change. Milbank Mem Fund Q 49(4):509–538 Organización Panamericana de la Salud (2019) Indicadores básicos 2019: Tendencias de la salud en las Américas. OPS, Washington, DC, 21 p PAHO-OMS (2015) Ultra-processed food and drink products in Latin America: TRENDS, impact on obesity, policy implications. PAHO, Washington, DC, 76 p Pérez-Ferrer C, McMunn A, Zaninotto P, Brunner EJ (2018) The nutrition transition in Mexico 1988-2016: the role of wealth in the social patterning of obesity by education. Public Health Nutr 21(13):2394–2401. https://doi.org/10.1017/S1368980018001167 Popkin BM (1993) Nutritional patterns and transitions. Popul Dev Rev 19:138–157 Popkin BM (1994) The nutrition transition in low-income countries: an emerging crisis. Nutr Rev 52:285–298. https://doi.org/10.1111/j.1753-4887.1994.tb01460.x Popkin BM (1998) The nutrition transition and its health implications in lower-income countries. Public Health Nutr 1(1):5–2. https://doi.org/10.1079/phn19980004 Popkin BM (2001) The nutrition transition and its relationship to demographic change. In: Nutrition and health in developing countries. Humana Press, Totowa, NJ, pp 427–445 Popkin BM (2002a) An overview of the nutrition transition and its health implications: the Bellagio meeting. Public Health Nutr 5(1A):93–103. https://doi.org/10. 1079/phn2001280

18 Popkin BM (2002b) The shift in stages of the nutrition transition in the developing world differs from past experiences! Public Health Nutr 5(1A):205–214. https://doi.org/10.1079/PHN2001295 Popkin BM (2004) The nutrition transition: an overview of world patterns of change. Nutr Rev 62:3–40. https:// doi.org/10.1111/j.1753-4887.2004.tb00084.x Popkin BM (2006) Technology, transport, globalization and the nutrition transition. Food Policy 31:554–569 Popkin BM (2009) Global changes in diet and activity patterns as drivers of the nutrition transition. In: Emerging societies-coexistence of childhood malnutrition and obesity, vol 63. Karger, New York, pp 1–14 Popkin BM (2011) Contemporary nutritional transition: determinants of diet and its impact on body composition. Proc Nutr Soc 70(1):82–91. https://doi.org/10. 1017/S0029665110003903 Popkin BM (2015) Nutrition transition and the global diabetes epidemic. Curr Diab Rep 15(9):64. https:// doi.org/10.1007/s11892-015-0631-4 Popkin BM (2017) Relationship between shifts in food system dynamics and acceleration of the global nutrition transition. Nutr Rev 75(2):73–82. https://doi.org/ 10.1093/nutrit/nuw064 Popkin BM, Gordon-Larsen P (2004) The nutrition transition: worldwide obesity dynamics and their determinants. Int J Obes Relat Metab Disord 28 (Suppl 3):S2–S9. https://doi.org/10.1038/sj.ijo. 0802804 Popkin BM, Reardon T (2018) Obesity and the food system transformation in Latin America. Obes Rev 19 (8):1028–1064. https://doi.org/10.1111/obr.12694 Popkin BM, Richards MK, Montiero CA (1996) Stunting is associated with overweight in children of four nations that are undergoing the nutrition transition. J Nutr 126(12):3009–3016. https://doi.org/10.1093/jn/ 126.12.3009 Popkin BM, Adair L, Ng S (2012) Global nutrition transition and the pandemic of obesity in developing countries. Nutr Rev 70(1):3–21. https://doi.org/10. 1111/j.1753-4887.2011.00456.x Pou SA, Díaz Mdel P, Osella AR (2012) Applying multilevel model to the relationship of dietary patterns and colorectal cancer: an ongoing case-control study in Córdoba, Argentina. Eur J Nutr 51(6):755–764. https://doi.org/10.1007/s00394-011-0255-7 Pou SA, Niclis C, Eynard AR, Díaz MP (2014a) Dietary patterns and risk of urinary tract tumors: a multilevel analysis of individuals in rural and urban contexts. Eur J Nutr 53(5):1247–1253. https://doi.org/10.1007/ s00394-013-0627-2 Pou SA, Niclis C, Aballay LR, Tumas N, Román MD, Muñoz SE, Coquet JB, Díaz MP (2014b) Cancer and its association with dietary patterns in Córdoba (Argentina). Nutr Hosp 29(3):618–628. https://doi. org/10.3305/nh.2014.29.3.7192

S. A. Pou et al. Pou SA, Del Pilar DM, De La Quintana AG, Forte CA, Aballay LR (2016) Identification of dietary patterns in urban population of Argentina: study on diet-obesity relation in population-based prevalence study. Nutr Res Pract 10(6):616–622. https://doi.org/10.4162/nrp. 2016.10.6.616 Pou SA, Tumas N, Sanchez Soria D, Ortiz P, Díaz MP (2017) Large-scale societal factors and noncommunicable diseases: Urbanization, poverty and mortality spatial patterns in Argentina. Appl Geogr 86:32–40. https://doi.org/10.1016/j.apgeog. 2017.06.022 Sievert K, Lawrence M, Naika A, Baker P (2019) Processed foods and nutrition transition in the Pacific: regional trends, patterns and food system drivers. Nutrients 11(6):E1328. https://doi.org/10.3390/ nu11061328 Tirado MC, Galicia L, Husby HM et al (2016) Mapping of nutrition and sectoral policies addressing malnutrition in Latin America. Rev Panam Salud Publica 40 (2):114–123 Tumas N, Niclis C, Aballay LR, Osella AR, Díaz MP (2014) Traditional dietary pattern of South America is linked to breast cancer: an ongoing case-control study in Argentina. Eur J Nutr 53(2):557–566. https://doi. org/10.1007/s00394-013-0564-0 Tumas N, Rodríguez Junyent C, Aballay LR, Scruzzi GF, Pou SA (2019) Nutrition transition profiles and obesity burden in Argentina. Public Health Nutr 22 (12):2237–2247. https://doi.org/10.1017/ S1368980019000429 United Nations, Population Division of the Department of Economic and Social Affairs (2017) Revision of World Population Prospects, United Nations, New York United Nations System, Standing Committee on Nutrition (2010) 6th report on the world nutrition situation– progress in nutrition. United Nations, 134 p Vandevijvere S, Jaacks LM, Monteiro CA et al (2019) Global trends in ultraprocessed food and drink product sales and their association with adult body mass index trajectories. Obes Rev 20(Suppl 2):10–19. https://doi. org/10.1111/obr.12860 Walls HL, Johnston D, Mazalale J, Chirwa EW (2018) Why we are still failing to measure the nutrition transition. BMJ Glob Health 3(1):e000657. https://doi.org/ 10.1136/bmjgh-2017-000657 Wells JC, Sawaya AL, Wibaek R et al (2020) The double burden of malnutrition: aetiological pathways and consequences for health. Lancet 395(10217):75–88. https://doi.org/10.1016/S0140-6736(19)32472-9 World Health Organization (2017) 10 facts on obesity. Available from: https://www.who.int/features/ factfiles/obesity/en/ World Health Organization (2018a). Obesity and overweight. Available from: https://www.who.int/newsroom/fact-sheets/detail/obesity-and-overweight

2

Nutrition Transition and Obesity Trends in Argentina Within the Latin American Context

World Health Organization (2018b) Noncommunicable diseases. Available from: https://www.who.int/en/ news-room/fact-sheets/detail/noncommunicablediseases World Health Organization (2018c) Noncommunicable diseases country profiles 2018. Available from: https://www.who.int/nmh/countries/en/ Zapata ME, Rovirosa A (2016) Carmuega. La mesa Argentina en las últimas dos décadas: cambios en el

19

patrón de consumo de alimentos y nutrientes 1996–2013. Ciudad Autónoma de Buenos Aires: Centro de Estudios sobre Nutrición Infantil—CESNI, 204 p Zapata ME, Rovirosa A, Carmuega E (2016) [Changes in the food and beverage consumption pattern in Argentina, 1996–2013]. Salud Colect 12(4):473–486. Spanish. https://doi.org/10.18294/sc.2016.936

3

Challenges and Economic Burden of Diabetes in Africa Camille Maadjhou Mba and Jean Claude Mbanya

Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Social and Financial Burden . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Challenges to Diabetes Management in Africa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Epidemiological transitions: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Access to Health Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Knowledge, Beliefs, and Health Seeking Behaviors in Africa . . . . . . . . . . . . . . . . . . . . . . . 24 Lack of Political Will . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Under-Allocation of Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Complications and Mortality Attributable to Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Prevalence and Incidence of Diabetes Complications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Disability and Mortality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Economic Burden of Diabetes Mellitus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Costs Attributable to Diabetes Mellitus in Africa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Purchasing Power Parity Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Direct Cost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Profile of African Countries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Indirect Cost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 C. M. Mba MRC Epidemiology Unit, University of Cambridge, Cambridge, UK Department of Public Health, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon J. C. Mbanya (*) Department of Internal Medicine and Specialties, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon e-mail: [email protected] # Springer Nature Switzerland AG 2020 J. Faintuch and S. Faintuch (eds.), Obesity and Diabetes, https://doi.org/10.1007/978-3-030-53370-0_3

21

22

C. M. Mba and J. C. Mbanya Intangible Cost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Cost of Diabetes Complications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Comparative Health Care Expenditures in Africa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 National Diabetes Programs (NDPs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Sustainable Development Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Universal Health Coverage (UHC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Abstract

Diabetes imposes a huge financial burden on affected individuals, their families, society, and country. Undesirable changes in lifestyle coupled with inadequate health care systems are some of the major drivers of diabetes burden in sub-Saharan Africa (SSA), where there will be the greatest increase of diabetes in the world of 143%, within the next 25 years. Only 5.5% of the GDP in SSA was spent on health in 2016 compared to the global estimate of 10%. Although SSA has witnessed a recent increase in diabetes incidence, the current diabetes-related expenditure of US$9.5 billion represents only 1% of the overall global expenditure on this disease. These include the direct costs associated with medical care, and the indirect costs resulting from cessation or reduced productivity because of disease-related disability/premature mortality. Indirect cost per patient with diabetes in SSA is higher than direct expenditures, contributing over 60% of the total cost. Keywords

Diabetes burden · Diabetes cost · Indirect cost · Direct cost · Sub Saharan Africa

constitute the majority of countries in sub-Saharan Africa (SSA) (WHO 2019a). Available estimates show that 7.1% of adults living in Africa or 33 million people suffer from diabetes, although in 2019 the International Diabetes Federation estimated that diabetes affected over 19 million people in the region, while an additional 45 million adults had impaired glucose tolerance (IGT) (IDF Diabetes Federation 2019a). Nigeria is among the top ten countries in the world with the highest number of people with IGT (8.2 million people). If current trends persist, both the number of people with type 2 diabetes (T2D) and IGT in SSA will increase by 143% by 2045; the highest global predicted increase. However, the true number could be much higher, given that as many as two thirds of those with the disease remain undiagnosed (IDF Diabetes Federation 2019a). This rising burden of diabetes in SSA has been triggered by increasing obesity and changing lifestyles in both rural and urban communities (Mbanya et al. 2014). As in other parts of the world, more than 90% of patients have type 2 diabetes with diagnosis often made late in the course of disease progression, or at the time of complications. Also, approximately 10,300 children and adolescents are diagnosed each year with type 1 diabetes (T1D) which carries a high mortality rate (IDF Diabetes Federation 2019a).

Introduction Social and Financial Burden Nearly 80% of noncommunicable disease (NCDs) related deaths including diabetes, occur in low- and middle- income countries, which

Delayed diagnosis and poor metabolic control contribute to the high morbidity and premature

3

Challenges and Economic Burden of Diabetes in Africa

mortality in the region (Dalal et al. 2011). The mortality rate is increasing and occurring at younger ages in SSA compared with the other regions; three of four deaths due to diabetes occur in the active age group less than 60 years old (IDF Diabetes Federation 2019a; Miranda et al. 2019). Total disability adjusted life-years (DALYs) due to diabetes increased by 126.4% between 1990 and 2017, and the Lancet Diabetes and Endocrinology Commission estimated that in 2015, the overall cost of diabetes in sub-Saharan Africa was US$19.45 billion, or 1.2% of cumulative gross domestic product (GDP) (Gouda et al. 2019; Atun et al. 2017). Despite progress in health coverage, access to medications especially insulin and quality healthcare facilities remain a challenge, with wide disparities between African countries (Mutyambizi et al. 2018). Poor access to insulin is the major cause of mortality in children with T1D (Atun and Gale 2015; Choukem et al. 2019). This has a huge financial implication for the economy of households and the already overburdened healthcare systems. Few African countries have a national diabetes plan and there is a lack of access to full coverage for essential health services (IDF Diabetes Federation 2019a). Due to the lack of primary data and the high proportion of undiagnosed diabetes to estimate the real-world cost of diabetes in the SSA, public health interventions have relied on results from modeling methods (Afroz et al. 2018). Africa’s health service delivery capacity has improved, yet this is still insufficient to meet current and future needs of the care of diabetes (WHO 2019b).

Challenges to Diabetes Management in Africa These challenges are of two magnitudes: the increase in diabetes growth and those related to the implementation of effective diabetes care in Africa (Fig. 3.1).

23

Epidemiological transitions: In the 1980s, diabetes was still uncommon in Africa, but today it has exploded in many communities. This trend in T2D has been strongly linked to obesity, suboptimal diet, and physical inactivity, resulting from the rapid epidemiologic shifts involving urbanization and changing lifestyles in both the rural and urban communities of SSA (Mbanya et al. 2014). The age-standardized diabetes prevalence increased in parallel with body mass index from 3.4 to 8.5% in men, and 4.1 to 8.9% in women between 1980 and 2014 (NCD Risk Factor Collaboration (NCD-RisC)—Africa Working Group 2017). Global rise in BMI is usually linked to the increase in BMI in rural communities, except in SSA where BMI rose faster among urban women, and at a similar rate among urban and rural men (NCD Risk Factor Collaboration (NCD-RisC) 2019). The expansion of supermarkets with access to highly processed food and sweetened beverages as well as reduced physical activity could be driving the rural-urban differences (Pastakia et al. 2017; Assah et al. 2011).

Access to Health Care Many African countries are not prepared to effectively manage diabetes and they provide only suboptimal care to patients. Early identification, management, and control are important determinants for the reduction of diabetes complications, thus leading to a substantial reduction of the economic burden (Atun and Gale 2015; Kapwata and Manda 2018). Timely diagnosis and prevention rely mostly on the availability of health care practitioners, regular screening, and management of comorbidities (Pastakia et al. 2017). The proximity of healthcare facilities has been strongly linked to increasing utilization of these services in developing countries, especially in rural communities (Feikin et al. 2009). Financial

24

C. M. Mba and J. C. Mbanya

Epidemiology in SSA:

Reasons for diabetes explosion in Africa

Health expenditure 1.2% of global expenditure

Increase obesity and changing lifestyles Poor diabetes awareness/ mispercepon

Only 9.5 billion spent on diabetes 59.6% undiagnosed

Potenal soluons

Roune clinical care

Inadequate healthcare systems Rural/urban disparies. Absence of region specific guidelines

Health seeking behaviours; tradional healers

36.7% out of pocket

Almost ½ million deaths in 2019

Community screening

Challenges

Trained personnel

Increase expenditure on diabetes research and management

Raise community awareness Educaon to change behaviours

Access to essenal medicaon and supplies Implementaon of Naonal Diabetes Programmes

Secondary prevenon

Fig. 3.1 Socioeconomic burden of diabetes and healthcare challenges in Africa (IDF Diabetes Federation 2019a; Choukem et al. 2019)

availability and accessibility of health services, transportation facilities, and cost, as well as the receptiveness of the healthcare professionals to the cultural and social norms of the community are equally relevant (Huerta Munoz and Källestål 2012). Poor access to insulin is the leading cause of mortality in patients with T1D (Gale 2006). Among the 400 million people globally who do not have access to basic healthcare services, the majority live in SSA (Sanogo et al. 2019).

patients to seek solely or as complementary care, the traditional healers (Choukem et al. 2019). Diverse knowledge, beliefs, and perceptions in addition to finances are key factors that influence a patient’s decision to seek medical advice during an illness. Moreover, misconceptions associated with hospital facilities contribute to increasing the total cost associated with diabetes, as some patients tend to be managed at home or seek traditional healers, thereby presenting to health facilities mostly at the time of complications (Choukem et al. 2019).

Knowledge, Beliefs, and Health Seeking Behaviors in Africa Lack of Political Will Obesity which is a major risk factor for T2D is still perceived by some people as a sign of wealth and good living, while physical activity like regularly walking is a sign of poverty. Although most patients recognize that health care facilities are the ideal places to turn to, it is not unusual for

There is still a lack of appropriate action taken by key decision leaders in SSA, in order to halt the progression of diabetes (Atun and Gale 2015). The misconception that diabetes is a disease of the rich and the elderly, hampers commitments to

3

Challenges and Economic Burden of Diabetes in Africa

mobilize adequate resources for the management of diabetes and its complications. In fact, less than 30% of African countries have operational integrated policies for diabetes care (Kengne et al. 2013).

Under-Allocation of Resources Inadequate financing of NCDs like diabetes constitutes a major barrier to the early diagnosis and management of diabetes complications (Atun and Gale 2015). Although infections, maternal and perinatal mortality continue to threaten African healthcare systems, the idea that infectious diseases should be controlled before tackling NCDs is mostly misleading. According to WHO estimates in 2015 infectious diseases, maternal, perinatal, and nutritional conditions accounted for 59.1% of all age total DALYs, while NCDs were responsible for 30.7% (WHO 2019a). In addition, NCDs are responsible for up to 37% of total loss of productivity in SSA, compared to only 27% for infectious diseases (WHO 2019b).

Complications and Mortality Attributable to Diabetes Noncommunicable diseases like diabetes and cardiovascular account for 41 million deaths each year; the leading cause of mortality globally. Over 85% of these deaths occur in low- and middle-income countries (WHO 2019a), and the acute and chronic complications associated with the disease make it very costly to manage (Kengne et al. 2013). Diabetes is a major cause of non-traumatic lower limb amputation, blindness, kidney failure, heart attacks, and stroke (IDF Diabetes Federation 2019a).

Prevalence and Incidence of Diabetes Complications Chronic complications of diabetes may be present at the time of diagnosis especially in patients with T2D, but can also appear soon after the diagnosis

25

in patients with T1D (IDF Diabetes Federation 2019a). In early 2000, macrovascular complications of diabetes were considered rare in Africa, with coronary heart disease affecting 5–8% of type 2 diabetic patients (Mbanya and Sobngwi 2003). However, there is increasing evidence suggesting an increase in the burden of cardiovascular disease in SSA (Kengne et al. 2013), as a result of poor glycemic control in addition to other cardiovascular risk factors such as high blood pressure and dyslipidemia (Kengne et al. 2005). Five percent of patients with diabetes have cerebrovascular accidents at diagnosis, and up to 9.5% and 25% of patients with type 1 and 2 diabetes respectively also have retinopathy at diagnosis. Depending on the glycemic control and duration of diabetes the prevalence of diabetic retinopathy varies between 13 and 55 %, with severe retinopathy representing 15% of all cases (Mbanya and Sobngwi 2003; Kengne et al. 2005). Eight to 49% of patients with diabetes exhibit nephropathy and neuropathy is present in 11–66% depending on the diagnostic method used (Dalal et al. 2011). Long-standing complications in patients with T1D do not differ greatly from those with T2D (Motala et al. 2001). Lower extremity amputation varies from 1.5 to 7% (Mbanya and Sobngwi 2003). Diabetes complications in Africa are increasing as the prevalence and incidence of diabetes continue to rise. In Ghana, the incidence of diabetes-related lower limb amputations increased from 0.6 per 1000 follow up years in 2010 to 10.9 in 2015 (Sarfo-Kantanka et al. 2019). This is in contrast to industrialized countries where the complication rates are reducing (IDF Diabetes Federation 2019a). The coexistence of multiple chronic complications of diabetes is common, like in Nigeria where 51.7% of patients with diabetes and renal complications also had the peripheral vascular disease (Agaba 2004). Interactions between peripheral damaged organs and infection occur in up to 53% of patients with diabetes (Dalal et al. 2011). Heavy investment in the health care system like dialysis units and coronary care units are necessary to take care of these diabetes-related complications.

26

Disability and Mortality In 2017, NCDs accounted for 80% of disabilities globally with diabetes being the fourth leading cause (Mbanya et al. 2014). The age-standardized DALY rates for diabetes are higher amongst men than women (Gouda et al. 2019). Disability and the premature mortality caused by diabetes occur at a younger age in SSA compared to other regions. Globally in 2019, diabetes was responsible for 366,200 deaths with 3 of 4 deaths occurring before 60 years whereas, in 2009, diabetes-related mortality was highest in the age group of 30–39 years (IDF Diabetes Federation 2019a, b). High blood pressure which is common in blacks, was found to be about twice more common in people with diabetes compared to age-matched controls, while dyslipidemia ranged from 16 to 89% and overweight 50–83%. Cardiovascular complications are amongst the leading cause of mortality from chronic complications in patients with T2D (Kengne et al. 2005). Although there is poor documentation on the causes of deaths in Africa, available estimates suggest that diabetes-related mortality ranges between 8 and 41% of all-cause mortality, and this is primarily due to acute complications and infections (Peer et al. 2014). In Cameroon, acute complications were the leading cause of mortality (22.2%) followed by cardiovascular complications (16.7%) and nephropathy (14.8%) (Foryoung et al. 2018). The life expectancy in children with T1D could be as low as 1% in Africa (Beran and Yudkin 2006). In South Africa, the predominant cause of mortality in patients with T1D is nephropathy, accounting for over 40% of all deaths (Gill et al. 2005). Table 3.1 shows the number of deaths in adults aged 20–79 years for some SSA countries.

Economic Burden of Diabetes Mellitus Three alternative approaches exist to estimate the economic burden of public health problems like

C. M. Mba and J. C. Mbanya

diabetes including the willingness to pay approach, the macroeconomic/production function approach, and the cost of illness approach (COI). The last one is the most commonly employed and takes into account the direct cost, indirect cost, and intangible cost (Fig. 3.2).

Costs Attributable to Diabetes Mellitus in Africa Since 2001, there has been a steady rise in the gross domestic product (GDP) of many sub-Saharan African countries, reaching its peak in 2014. In 2016, the mean GDP per capita spent by SSA countries was equivalent to US$1511.3 with a wide range from US$282.1 in Burundi to US$15,077.8 in Seychelles (The World Bank 2019). Overall, less than 5.6% of the GDP was spent on healthcare in the low- and middleincome countries of SSA. The World Health Organization (WHO) estimates that up to 11 million Africans fall into poverty each year, due to high out of pocket payments for healthcare (WHO 2019b). Few studies have quantified the economic burden of diabetes at the regional level. A major difficulty in collating data for the cost of illness studies is that authors report on only one type of cost; mostly the direct cost (Afroz et al. 2018). In South Africa, where the diabetes age-adjusted prevalence is 12.7%, mean diabetes-related expenditure was US$1245.0 per patient (Table 3.1), while in Benin, the age-adjusted diabetes prevalence was 1% and mean expenditure was US$163.8 pp. Diabetes costs have increased from 1.4 billion in 2010 to 9.5 billion in 2019. This is due to both an increase in the prevalence of diabetes by 57%, and an increase in the cost of persons living with diabetes from US$222.6 to US$509 (IDF Diabetes Federation 2019a, b). According to current reports, the cost of care for people with diabetes in Africa accounts for 12.5% of healthcare expenses, with the highest percentage in South Africa (23.0%) (IDF Diabetes Federation 2019a).

3

Challenges and Economic Burden of Diabetes in Africa

27

Table 3.1 Prevalence estimates and economic indicators of diabetes for some African countries

Country Benin Botswana Burkina Faso Cameroon Central African Republicd Chadd Comoros Cote d’Ivoired Equatorial Guinead Ethiopia Gabond Gambia Ghana Kenya Mauritania Mozambique Namibia Nigerd Nigeria Sierra Leoned South Africa Tanzania Uganda Zimbabwe

Mean diabetes-related expenditure per person (20–79) with diabetes (PPP)a 163.8 1417.6 177.6

GDP per capita (current US$)b 829.5 7893.2 642.4

6.0 6.0

311.3 72.0

1421.6 449.8

68 24

13,744.3 3162.9

6.0 12.3 2.4

135.3 173.6 327.0

664.3 1320.5 1557.2

30 59 70

5706.5 357.4 5207.1

6.0

1305.8

9738.4

301

491.5

4.3 6.0 1.9 2.5 3.1 7.1 3.3 4.5 2.4 3.1 2.4

113.3 1015.2 119.3 262.2 324 213.0 101.8 1871.8 87.7 468.6 587.9

768.4 7212.5 679.8 2025.9 1568.2 1145.5 461.4 5646.5 375.9 1968.6 499.4

25 204 23 67 77 49 21 447 29 74 66

23,156.8 922.6 193.3 5397.8 8080.5 1776.5 9485.0 1095.3 3180.6 63,957.7 19.3

12.7 5.7 2.5 1.8

1245.0 170.1 191 540.9

6132.5 1004.8 631.5 1602.4

499 34 39 110

89,834.4 18,031.7 6288.0 2621.9

Age-adjusted diabetes prevalence for the age group 20–79 years (%)a 1.0 5.8 7.3

Current Health Expenditure per capita in US$c 31 466 44

Number of diabetesrelated deaths (20–79)a 692.8 1674.5 9675.2

a

IDF Atlas, 2019 (IDF Diabetes Federation 2019a) World Bank indicators, 2017 (The World Bank 2019) c WHO Global expenditure database, 2017 (WHO 2019c) d Indicates absence of in-country data sources on diabetes b

Purchasing Power Parity Calculations Nineteen million adults with diabetes recorded in Africa in 2019 resulted in a total economic cost of US$9.5 billion. Using the 2005 purchasing power parity (PPP), Kirigia and colleagues estimated the cost of diabetes per patient at Int$3633, giving a total burden of Int$25.51 billion, with indirect cost contributing 68% of it (Kirigia et al. 2009). Consistent with this, other reviews have reported

the indirect costs of diabetes per patient to be higher than the direct costs (Mutyambizi et al. 2018). Nevertheless, Bommer and colleagues found a lower contribution of indirect cost (44.4%) (Bommer et al. 2017). Cost of medication and hospitalization are the major causes of direct expenses (Afroz et al. 2018). A review reported the cost of medication to contribute as high as 50% of the total cost (Mutyambizi et al. 2018).

28

C. M. Mba and J. C. Mbanya

Economic Burden

Willingness to pay approach

Direct cost

Direct Medical Cost • Medication cost • Hospitalisation cost • Outpatient consultation • Diagnosis cost

Cost of Illness (COI) approach

Indirect cost (reduced or cessation of work)

Direct non-Medical Cost • Transportation cost • Hotel accommodation for caretaker • Food

Macroeconomic approach

Intangible cost (Reduced quality of life)

Disease related disability

Premature mortality

Fig. 3.2 Measurements approaches to the economic burden of diabetes (Adapted from Kirigia et al. (2009))

Direct Cost

Profile of African Countries

The direct cost of a disease refers to resources used for the treatment of the disease regardless of whether they are born by patients themselves, by private or public payers, or by the government (IDF Diabetes Federation 2019a). This is usually divided into the direct medical cost which are expenses, borne as a result of direct medical treatment like medications, outpatient visits, laboratory tests, and hospitalizations. The second is the direct nonmedical cost which are expenses incurred as a result of transportation, food, lodgment. In COI studies, cost of medications, diagnostic cost, cost of the consultation, and inpatient cost is the most commonly reported (Mutyambizi et al. 2018).

The direct cost of diabetes differs greatly between African countries with reported costs estimated from Int$3.5 billion to Int$4.5 billion and over US$10.8 billion per annum (Mutyambizi et al. 2018; Bommer et al. 2017) (Table 3.2). There are inconsistent findings of the major contributors, with some reviews reporting the cost of hospitalization as predominant, and other medication costs (Mutyambizi et al. 2018; Afroz et al. 2018). For outpatients in Nigeria, the cost of medication varied between Int$420.63 to Int $1025.00 per patient per annum for type 1 and 2 diabetes respectively, thus contributing as high as 90% of all treatment cost. For hospitalized patients, the cost of medication ranged from Int

3

Challenges and Economic Burden of Diabetes in Africa

29

Table 3.2 Summary of studies on diabetes costs from Africa (adapted from Mapa et al. (2019)) Year of costing 2019 2018 2015 2015

2013– 2015

2013 2011– 2012 2009– 2011 2010 2009 2009 2005 2005

2003– 2004 1995

Setting/Reference Africa (IDF Diabetes Federation 2019a) Africa (Mutyambizi et al. 2018) Africa (Bommer et al. 2017) Guinea (Alouki et al. 2015) Mali Benin Burkina Faso Benin (Ogle et al. 2016) Burkina Faso Central African Republic Ivory coast Malawi Mauritania Morocco (Boutayeb et al. 2013) Nigeria (Suleiman and Festus 2015) Cameroon (Ngassam et al. 2012) Nigeria (Abdulganiyu and Fola 2014) Mali (BermudezTamayo et al. 2017) Ghana (Quaye et al. 2015) Sudan (ElrayahEliadarous et al. 2010) Africa (Kirigia et al. 2009) Nigeria (Suleiman et al. 2006) Sudan (Elrayah et al. 2005)

Perspectives Societal

Type of diabetes 1 and 2

Direct cost (US$)

Indirect costs (US$)

All

1 and 2 1 and 2

Int$3.5 billion to Int$4.5 billion per annum 10.8 billion

All

8.6 billion

Patients

2

126–1093 pp

Patients Patients Patients Family

2 2 2 1

137–869 pp 212–828 pp 224–859 pp 588 pp

Family Family

1 1

1185 pp 737 pp

Family Family Family Societal

1 1 1 1 and 2

Societal

2

553 pp 999 pp 630 pp 259–830 pp or 0.47 billion to 1.5 billion 1.64 billion

Patients

2

148 pp

Patients and hospital Patient

2

1.5 million

2

365.48 pp

Health system Patients

1 and 2

423 pp

2

175a

Societal

1 and 2

Int$17.41 billion

Patients and hospital Patients

1 and 2

1.07 billion

1

283b

Total cost (US $) 9.5 billion

19.4 billion

1113 pp or 2 billion

762.20 pp

1127 pp

Int$8.1 billion

Int $25.51 billion

Abbreviation: pp per person Unless otherwise stated, costs are annual cost in US$ Common perspectives used in COI studies are the patient perspective, the employer perspective (loss of productivity), health system perspective, government perspective and societal perspective Int$: International dollar (local cost converted to the purchasing power of one US$) a Annual cost of minimum care diabetes supplies b Median cost

30

$553 to 1438 per admission in Nigeria and Int$80 to 461 in South Africa. In Cameroon, the cost of medication was estimated at I$3.9 per patient per month (Mutyambizi et al. 2018). The greatest expense incurred for diabetes medications comes from insulin. Indeed, the annual treatment for diabetes with insulin is US$104.4 compared to US$26.9 with metformin (Atun et al. 2017). Several factors are associated with the direct cost of diabetes include socioeconomic factors like age, level of education and income class, factors related to diabetes like duration of diabetes, number of complications, mode of treatment, hospitalizations, and surgery (Afroz et al. 2018). As shown in Table 3.2, the cost of T1D is consistently higher than for type 2 diabetes across the studies.

Indirect Cost The indirect cost is the opportunity cost resulting from reduced or loss of productivity at work by patients and their accompanying persons, because of the disease-related disability or premature mortality (Afroz et al. 2018). This includes the productive time lost for medical reasons like traveling for medical consultations and waiting to be admitted, hospital admissions for complications, absence from work for diseaserelated disability, and years of work lost due to premature deaths. Depending on the approach used to calculate the indirect cost of diabetes, the economic burden might be overstated. Some methods estimate the indirect cost for the unemployed while others use a more conservative approach like the friction-cost approach (Van den Hout 2010). The COI study in 2015 used four sources of indirect costs: labor-force drop out; mortality; absenteeism; and presenteeism (Bommer et al. 2017). Globally, the first two contribute 48.5% and 45.5% respectively of indirect cost, however, this is different in LMICs where mortality dominates, contributing 63.6% of the indirect cost in middle-income countries and 90.6% in low-income countries. As shown in Table 3.2, the annual indirect cost of diabetes per patient

C. M. Mba and J. C. Mbanya

was estimated at US$762.20 in Mali, for an annual total cost per patient of US$365.48, while in Morocco, the indirect cost per patient per month was US$1113 (Bermudez-Tamayo et al. 2017; Boutayeb et al. 2013). Because most studies report only on the direct cost, there is a dearth of information on the indirect cost of diabetes in Africa. Nonetheless, its contribution to total cost could contribute to over 60% of the total cost (Kirigia et al. 2009; Mapa-Tassou et al. 2019).

Intangible Cost Intangible cost relates to the reduced quality of life as a result of the physical, psychological, and social handicap of disease. The quality of life can be severely affected by chronic diseases and examples include pain, worry, anxiety, loss of independence, and lack of participation in social events (Afroz et al. 2018). Intangible costs are the most difficult to assess given that they are related to emotions. Because the quality of life is difficult to express in terms of money, many studies do not report on the intangible cost. Intangible cost of diabetes may range between US$30.8 per month if the patient had no complications, to US$143.9 if four or more complications were present. If patients had blood glucose levels within targets, the intangible cost was estimated at 10.3 per month, compared to US$41.1, if poorly controlled, with an annual estimate of US$496.7 (Afroz et al. 2018).

Cost of Diabetes Complications The major contributor to direct costs for diabetesrelated complications is hospitalization, and for indirect cost are absenteeism, disability, and premature mortality. There is a linear relationship between expenditures and the number of complications present. According to the International Diabetes Federation estimates, the treatment of diabetes-related complications accounts for over 50% of the direct cost attributable to diabetes, and this expenditure is highest in the

3

Challenges and Economic Burden of Diabetes in Africa

60–70 years age group (IDF Diabetes Federation 2019a). Nephropathy, diabetic foot, and stroke are the complications associated with the highest expenses in Africa (Mutyambizi et al. 2018). Patients with diabetes are likely to spend up to four times more if they have diabetes-related complications compared to those with no complication, and this varies greatly by countries. In Mali, up to Int$1346.5 per patient was spent on nephropathy while only Int$33.03 was spent in Guinea. For acute complications like diabetic ketoacidosis, the cost of management differs in those with and without chronic complications. In Guinea, the cost of treatment for diabetic ketoacidosis ranged from Int$22.1 to Int$39.2, and in Burkina Faso from Int$628.27 to Int $1085.4 (Mutyambizi et al. 2018). Mean annual health expenditures for people with four or more complications are expected to be about 20 times more than in people without complications (IDF Diabetes Federation 2019a). Consistent with this, the presence of one or more complications increased the cost ratio by 1.1 for retinopathy and up to 4.3 for an infected diabetes foot in another study. This is because, in Africa, foot complications in patients with diabetes often progress to infection or gangrene, resulting in longer hospitalizations and higher mortality rates (Mutyambizi et al. 2018).

Comparative Health Care Expenditures in Africa In 2016, 5.5% of the GDP in Africa was spent on health against 10% at the global level, with SSA having the highest out of pocket expenses (36.7%) (WHO 2019b; The World Bank 2019). In SSA, the GDP percent spent on health is not related to the national expenditure. For example, Sierra Leone with GDP per capita of US$501.4 spent 16.53% of its budget on healthcare, while others like Equatorial Guinea and Nigeria having a GDP of US$9738.4 and 1968.6 spent only 3.38% and 3.35% respectively. Similarly, out of pocket expenses on health care were highest in

31

Equatorial Guinee and Nigeria (72.83% and 75.21% respectively) (WHO 2019c). Globally, at least US$760 billion is expected to be spent on diabetes annually, and it could reach US$845 billion by 2045 (IDF Diabetes Federation 2019a). The expenditure per person in high-income countries (US$5339) was over 30-folds and almost sevenfold higher than in low- and middle-income countries respectively in 2019. Reduced or missed production opportunities due to diabetes contribute an additional 35% to the annual global health expenditures. Overall, direct expenses on diabetes have increased by 4.5% over the last 2 years, and it is predicted to increase by 11.2% over the next 25 years (IDF Diabetes Federation 2019a). It is possible that the real estimates are more important as actual projections are conservative, and based on the assumption that diabetes prevalence and expenditures are not changing. One can find substantially higher estimates for the global economic burden of diabetes at US$1.31 trillion, equivalent to 1.8% of the world GDP, with indirect cost contributing 34.7% of the overall burden in a COI study of 2015 (Bommer et al. 2017). In 2015, North America had the highest economic burden at US$499.40 billion (2.6% of its total GDP), while Africa had the lowest diabetesrelated expenditure; US$9.45 billion (1.2% of its total GDP). The contribution of the indirect cost was more important in high-income countries compared to LMICs (40.0% versus 33.5%) (Bommer et al. 2017). While the cost of medication is the major contributor to direct cost in Africa, there are conflicting reports between the cost medication or cost of hospitalization at the global level (Ng et al. 2014). Indirect cost contributed as high as 44.6% in SSA and 57.4% in South Asia as opposed to only 21.9% in Latin America and the Caribbean, although there is a report of a higher contribution of the indirect cost of 68% to the total cost in SSA (Bommer et al. 2017). (Kirigia et al. 2009). The lowest annual expenditure per person spent in SSA was in the Central African Republic, with similar estimates in Bangladesh (US$64), and Nepal (US$80). Overall, slightly higher expenditure was spent in 2019 in women than

32

C. M. Mba and J. C. Mbanya

Countries with the lowest GDP have the highest burden of NCDs in terms of DALYs, therefore if nothing is done, the rapid increase in diabetes will badly affect the African region. The potential strategies to address the economic burden of diabetes are listed below.

integrated policies for the management of diabetes and other NCDs (Kengne et al. 2013). Given that over 70% of deaths globally are due to NCDs, there is value in investing in strengthening the health care system and undertake more translational research to reduce the burden of diabetes (WHO 2019a). Furthermore, because diabetes mortality is highest in low-income countries, prioritization of the limited resources using costeffective strategies, like the WHO Best Buys interventions (e.g., taxation on alcohol and tobacco products) to change behaviors may improve health outcomes (Atun et al. 2017; Kengne et al. 2013).

National Diabetes Programs (NDPs)

Universal Health Coverage (UHC)

Early management and lifestyle changes can delay or prevent T2D in 80% of individuals (IDF Diabetes Federation 2019a). Therefore, the development and implementation of diabetes programs may reduce the incidence of diabetes and mortality. Unfortunately, less than one-third of SSA countries have a national diabetes plan (IDF Diabetes Federation 2019a). Important areas for the focus of NDPs are conducting community cost-effective interventions, aiming at raising awareness on diabetes and its risk factors, increasing physical activity, losing weight, eating healthily, along with routine screening and clinical care, and access to essential medication and supplies.

Most countries in SSA do not have a national health care insurance coverage, and therefore out of pocket payment of care limits access for individuals with low income. Such an objective could be achieved by ensuring an equitable tax payment system, and compulsory health insurance (Sanogo et al. 2019).

men across all the regions (US$382.6 billion versus US$377.6 billion) and this difference is predicted to be maintained over the years (IDF Diabetes Federation 2019a).

Perspectives

Sustainable Development Goals The third UN summit in New York in September 2018 recognized the challenges posed by diabetes and other NCDs on the socioeconomic development. To achieve the 2030 targets related to sustainable development goal 3, especially item 3.4 which aims at reducing premature mortality from NCDs by at least 33%, there is a need for governments, leaders, and stakeholders in SSA to urgently react to the threat imposed by diabetes and other NCDs. SSA healthcare systems continue to prioritize infectious diseases and currently, less than 30% of ministries in SSA have

References Abdulganiyu G, Fola T (2014) What is the cost of illness of type II diabetes mellitus in a developing economy? Int J Pharm Pharm Sci 6:5 Afroz A, Alramadan MJ, Hossain MN, Romero L, Alam K, Magliano DJ et al (2018) Cost-of-illness of type 2 diabetes mellitus in low and lower-middle income countries: a systematic review. BMC Health Serv Res 18(1):972 Agaba EI (2004) Characteristics of type 2 diabetics presenting with end stage renal disease at the Jos University Teaching Hospital, Nigeria. West Afr J Med 23(2):142–145 Alouki K, Delisle H, Besançon S, Baldé N, Sidibé-Traoré A, Drabo J et al (2015) Simple calculator to estimate the medical cost of diabetes in sub-Saharan Africa. World J Diabetes 6(16):1312–1322 Assah FK, Ekelund U, Brage S, Mbanya JC, Wareham NJ (2011) Urbanization, physical activity, and metabolic health in sub-Saharan Africa. Diabetes Care 34 (2):491–496 Atun R, Gale EAM (2015) The challenge of diabetes in sub-Saharan Africa. Lancet Diabetes Endocrinol 3 (9):675–677

3

Challenges and Economic Burden of Diabetes in Africa

Atun R, Davies JI, Gale EAM, Bärnighausen T, Beran D, Kengne AP et al (2017) Diabetes in sub-Saharan Africa: from clinical care to health policy. Lancet Diabetes Endocrinol 5(8):622–667 Beran D, Yudkin JS (2006) Diabetes care in sub-Saharan Africa. Lancet 368(9548):1689–1695 Bermudez-Tamayo C, Besançon S, Johri M, Assa S, Brown JB, Ramaiya K (2017) Direct and indirect costs of diabetes mellitus in Mali: a case-control study. PLoS One 12(5):e0176128 Bommer C, Heesemann E, Sagalova V, Manne-Goehler J, Atun R, Bärnighausen T et al (2017) The global economic burden of diabetes in adults aged 20-79 years: a cost-of-illness study. Lancet Diabetes Endocrinol 5 (6):423–430 Boutayeb W, Lamlili MEN, Boutayeb A, Boutayeb S (2013) Estimation of direct and indirect cost of diabetes in Morocco. J Biomed Sci Eng 06(07):732–738 Choukem SP, Dimala CA, Maadjhou C, Mbanya JC (2019) Diabetes management in Africa. In: Rodriguez-Saldana J (ed) The diabetes textbook. Springer, Cham, pp 273–288 Dalal S, Beunza JJ, Volmink J, Adebamowo C, Bajunirwe F, Njelekela M et al (2011) Non-communicable diseases in sub-Saharan Africa: what we know now. Int J Epidemiol 40(4):885–901 Elrayah H, Eltom M, Bedri A, Belal A, Rosling H, Östenson C-G (2005) Economic burden on families of childhood type 1 diabetes in urban Sudan. Diabetes Res Clin Pract 70(2):159–165 Elrayah-Eliadarous H, Yassin K, Eltom M, Abdelrahman S, Wahlström R, Ostenson C-G (2010) Direct costs for care and glycaemic control in patients with type 2 diabetes in Sudan. Exp Clin Endocrinol Diabetes 118(4):220–225 Feikin DR, Nguyen LM, Adazu K, Ombok M, Audi A, Slutsker L et al (2009) The impact of distance of residence from a peripheral health facility on pediatric health utilisation in rural western Kenya. Trop Med Int Health 14(1):54–61 Foryoung JB, Ditah C, Fon PN, Mboue-Djieka Y, Nebongo DN, Mbango ND et al (2018) Long-term mortality in outpatients with type 2 diabetes in a reference hospital in Cameroon: a retrospective cohort study. BMJ Open 8(2):e019086 Gale EAM (2006) Dying of diabetes. Lancet 368 (9548):1626–1628 Gill GV, Huddle KRL, Monkoe G (2005) Long-term (20 years) outcome and mortality of Type 1 diabetic patients in Soweto, South Africa. Diabetes Med 22 (12):1642–1646 Gouda HN, Charlson F, Sorsdahl K, Ahmadzada S, Ferrari AJ, Erskine H et al (2019) Burden of non-communicable diseases in sub-Saharan Africa, 1990–2017: results from the Global Burden of Disease Study 2017. Lancet Glob Health 7(10):e1375–e1387 Huerta Munoz U, Källestål C (2012) Geographical accessibility and spatial coverage modeling of the primary

33 health care network in the Western Province of Rwanda. Int J Health Geogr 11:40 IDF Diabetes Federation (2019a) IDF Diabetes Atlas, 9th ed. International Diabetes Federation, Brussels (cited 2019 Dec 19). http://www.diabetesatlas.org/ IDF Diabetes Federation (2019b) International diabetes atlas, 4th ed. International Diabetes Federation, Brussels, Belgium 2009 (cited 2019 Dec 19). https:// www.idf.org/e-library/epidemiology-research/diabe tes-atlas/21-atlas-4th-edition.html Kapwata T, Manda S (2018) Geographic assessment of access to health care in patients with cardiovascular disease in South Africa. BMC Health Serv Res 18 (1):197 Kengne AP, Amoah AGB, Mbanya J-C (2005) Cardiovascular complications of diabetes mellitus in sub-Saharan Africa. Circulation 112(23):3592–3601 Kengne AP, June-Rose Mchiza Z, Amoah AGB, Mbanya J-C (2013) Cardiovascular diseases and diabetes as economic and developmental challenges in Africa. Prog Cardiovasc Dis 56(3):302–313 Kirigia JM, Sambo HB, Sambo LG, Barry SP (2009) Economic burden of diabetes mellitus in the WHO African region. BMC Int Health Hum Rights 9:6 Mapa-Tassou C, Katte J-C, Mba Maadjhou C, Mbanya JC (2019) Economic impact of diabetes in Africa. Curr Diabetes Rep 19(2):5 Mbanya J-C, Sobngwi E (2003) Diabetes in Africa. Diabetes microvascular and macrovascular disease in Africa. J Cardiovasc Risk 10(2):97–102 Mbanya JC, Assah F, Saji J, Atanga EN (2014) Obesity and type 2 diabetes in Sub-Sahara Africa. Curr Diabetes Rep 14:1–8 Miranda JJ, Barrientos-Gutiérrez T, Corvalan C, Hyder AA, Lazo-Porras M, Oni T et al (2019) Understanding the rise of cardiometabolic diseases in low- and middle-income countries. Nat Med 25(11):1667–1679 Motala AA, Pirie FJ, Gouws E, Amod A, Omar MAK (2001) Microvascular complications in South African patients with long-duration diabetes mellitus. S Afr Med J 91(11):987–992 Mutyambizi C, Pavlova M, Chola L, Hongoro C, Groot W (2018) Cost of diabetes mellitus in Africa: a systematic review of existing literature. Glob Health 14(1):3 NCD Risk Factor Collaboration (NCD-RisC) (2019) Rising rural body-mass index is the main driver of the global obesity epidemic in adults. Nature 569 (7755):260–264 NCD Risk Factor Collaboration (NCD-RisC)—Africa Working Group (2017) Trends in obesity and diabetes across Africa from 1980 to 2014: an analysis of pooled population-based studies. Int J Epidemiol 46(5): 1421–1432 Ng CS, Lee JYC, Toh MP, Ko Y (2014) Cost-of-illness studies of diabetes mellitus: a systematic review. Diabetes Res Clin Pract 105(2):151–163 Ngassam E, Nguewa J-L, Ongnessek S, Foutko A, Mendane F, Balla V et al (2012) P318 Cout de la

34 prise en charge du diabète de type 2 a l’hopital central de yaounde. Diabetes Metab 38:A105 Ogle GD, Kim H, Middlehurst AC, Silink M, Jenkins AJ (2016) Financial costs for families of children with Type 1 diabetes in lower-income countries. Diabetes Med 33(6):820–826 Pastakia SD, Pekny CR, Manyara SM, Fischer L (2017) Diabetes in sub-Saharan Africa—from policy to practice to progress: targeting the existing gaps for future care for diabetes. Diabetes Metab Syndr Obes 10:247–263 Peer N, Kengne A-P, Motala AA, Mbanya JC (2014) Diabetes in the Africa Region: an update. Diabetes Res Clin Pract 103(2):197–205 Quaye EA, Amporful EO, Akweongo P, Aikins MK (2015) Analysis of the financial cost of diabetes mellitus in four cocoa clinics of Ghana. Value Health Reg Issues 7:49–53 Sanogo NA, Fantaye AW, Yaya S (2019) Universal health coverage and facilitation of equitable access to care in Africa. Front Public Health 7:102 Sarfo-Kantanka O, Sarfo FS, Kyei I, Agyemang C, Mbanya JC (2019) Incidence and determinants of diabetes-related lower limb amputations in Ghana,

C. M. Mba and J. C. Mbanya 2010–2015—a retrospective cohort study. BMC Endocr Disord 19(1):27 Suleiman IA, Festus JA (2015) Cost of illness among diabetes mellitus patients in Niger Delta, Nigeria. J Pharm Health Serv Res 6:53–60 Suleiman IA, Fadeke OF, Okubanjo OO (2006) Pharmacoeconomic evaluation of anti-diabetic therapy in a Nigerian Tertiary Health Institution. Ann Afr Med 5:132–137 The World Bank (2019) Data indicators (cited 2019 Dec 19). https://data.worldbank.org/indicator Van den Hout WB (2010) The value of productivity: human-capital versus friction-cost method. Ann Rheum Dis 69(1):89–91 WHO (2019a) NCD mortality and morbidity (cited 2019 Dec 19). http://www.who.int/gho/ncd/mortality_mor bidity/en/ WHO (2019b) A heavy burden: the productivity cost of illness in Africa. WHO, Regional Office for Africa (cited 2019 Dec 19). https://www.afro.who.int/ publications/heavy-burden-productivity-cost-illnessafrica WHO (2019c) Global health expenditure database 2017 (cited 2019 Dec 19). Available from: https://apps.who. int/nha/database/Select/Indicators/en

4

Brown Adipose Tissue in Obesity and Diabetes Martín Alcalá, Laura Herrero, Dolors Serra, and Marta Viana

Contents Adipose Tissue Classification: Types, Location, and Function . . . . . . . . . . . . . . . . . . . . . . 37 Clinical Measurement of Brown Adipose Tissue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Positron Emission Tomography (PET) Imaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Magnetic Resonance (MR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preclinical Imaging Techniques (Thermometry, Ultrasound, and Near-Infrared Spectroscopy) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

38 38 39 39

Secretory Activity of Brown Adipose Tissue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Brown Adipokines or “Batokines” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Brown Adipose Tissue Signaling to Other Tissues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Neuroendocrine Regulation of Brown Adipose Tissue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Sympathetic BAT Innervation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Sensory Innervation of BAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Adipose Tissue Dysfunction in Obesity and Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sick Fat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The WAT Expandability Hypothesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Brown Adipose Tissue in Obesity and Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

46 46 46 47

M. Alcalá · M. Viana (*) Department of Chemistry and Biochemistry, Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Madrid, Spain e-mail: [email protected] L. Herrero · D. Serra Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, Institut de Biomedicina de la Universitat de Barcelona (IBUB), Universitat de Barcelona, Barcelona, Spain Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain # Springer Nature Switzerland AG 2020 J. Faintuch and S. Faintuch (eds.), Obesity and Diabetes, https://doi.org/10.1007/978-3-030-53370-0_4

35

36

M. Alcalá et al. Therapeutic Perspectives for Brown and White Adipose Tissue Manipulation . . . Chemical Activation of BAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bat Transplantation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Direct BAT Grafting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Promises and Pitfalls of Human BAT Transplantation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

47 47 48 49 49

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Abstract

The scientific community is leading efforts to find efficient therapies for obesity and diabetes, which led to the rediscovery in 2009 of the presence of functional brown adipose tissue (BAT) depots in adult humans. In this chapter, we describe the main characteristics of this tissue and the image techniques available for its detection. In addition, we discuss the secretory capacity of BAT that is responsible for crosstalk with other organs and confers a regulatory role in several processes beyond the canonical generation of heat. Finally, we explain the mechanisms through which obesity and diabetes interrupt the physiological role and development of BAT and we summarize the latest results of the studies that use BAT transplant as a new therapy in the treatment of metabolic diseases.

Abbreviations Ad-MSCs Adipose tissue derivedmesenchymal stem cells ARC Arcuate nucleus BAT Brown adipose tissue BMP Bone morphogenetic protein BOLD Blood-oxygen-level-dependent 14 14 C-FBnTP C-fluorobenzyl triphenyl phosphonium CGRP Calcitonin gene-related peptide 11 C-MBR (S,S)-O-methyreboxetine CNS Central nervous system 11 C-PBR28 Peripheral benzodiazepine receptor tracker CT Computational tomography CXCL14 Chemokine (C-X-C motif) ligand 14 12, 12, 13-dyhidroxy-9Z13-diHOME octadecenoic acid

DIO DMH ECM eWAT FA FGF21 18 F-FDG 18 F-THA GDF15 HFD IL-6 iPSCs IRT LepRB MnPO MR MSCs NE NGF NIRTRS NOD NRG4 NTS PET POMC PRV scWAT SNS SUV TH TNFα UCP1 VEGF-α WAT

Diet-induced obesity Dorsomedial hypothalamic nucleus Extracellular matrix Epididymal white adipose tissue Fatty acids Fibroblast growth factor 21 18 F-fluorodeoxyglucose 14 (R,S)-fluoro-6thiaheptadecanoic acid Growth differentiation factor-15 High-fat diet Interleukin-6 Induced pluripotent stem cells Infrared thermography Leptin receptor Median preoptic subnucleus Magnetic resonance Mesenchymal stem cells Norepinephrine Nerve growth factor Near-infrared time-resolved spectroscopy Non-obese diabetic Neuregulin 4 Nucleus of solitary track Positron emission tomography Precursor proopiomelanocortin Pseudorabies virus Subcutaneous white adipose tissue Sympathetic nervous system Standardized uptake value Tyrosine hydroxylase Tumor necrosis factor α Uncoupling protein 1 Vascular endothelial growth factor-α White adipose tissue

4

Brown Adipose Tissue in Obesity and Diabetes

Adipose Tissue Classification: Types, Location, and Function Traditionally, adipose tissue has been classified by its energy profile. According to this classification, white adipose tissue (WAT) is composed of adipocytes that are mainly comprised of a single, large lipid droplet that constrains the nuclei against the plasma membrane. This tissue mainly acts as an energy store, although it also has a secretory role, exerting autocrine, paracrine, and endocrine functions. In humans, there are major depots in subcutaneous (abdominal, gluteofemoral) and visceral regions (omental, mesenteric, mediastinal, and epicardial) while inclusions of minor depots can be observed in organs such as the liver, muscle, or kidneys. Brown adipose tissue (BAT) has a completely distinct developmental origin as it comes from Pax7+/Myf5+ stem cells (in contrast to WAT that comes from stem cells that do not express either of these progenitors). The whole tissue is densely vascularized and innervated, but its main feature is the presence of multilocular adipocytes that

Fig. 4.1 Brown adipose tissue detection and activation by 18 F-FDG uptake. (a) PET images of a 21-year-old man who was given a placebo (left) or 200 mg of the β3-AR agonist mirabegron (right). Twelve male subjects were

37

contain small lipid droplets and have an elevated mitochondrial content, which is responsible for its thermogenic function. This is due to the characteristic presence of uncoupling protein 1 (UCP1). UCP1 is a channel located in the inner mitochondrial membrane that returns protons pumped by the electron transport chain from the intermembrane space to the mitochondrial matrix, avoiding their use by ATP synthase, so the released energy is dissipated as heat. In humans, it was thought that the presence of this tissue was mainly restricted to interscapular and perirenal regions in babies and infants, that require this thermogenic function to maintain body temperature until they acquire the shivering reflex. However, in 2009, five independent researchers rediscovered the presence of BAT in cervical, supraclavicular, para-vertebral, suprarenal, and periaortic regions in adults and, more importantly, determined that this tissue can still be activated. This discovery rapidly boosted interest in BAT as a potential therapeutic tool against metabolic diseases (Cypess et al. 2009; Zingaretti et al. 2009; van Marken Lichtenbelt et al. 2009; Virtanen et al. 2009; Saito et al. 2009) (Fig. 4.1).

given a placebo or 200 mg mirabegron. (b) BAT metabolic activity as reflected by 18F-FDG uptake. Reproduced with permission from Cypess et al. (2015)

38

Finally, it is known that under certain conditions, such as cold or a high-fat diet (HFD), in some WAT depots a population of UCP1 positive adipocytes can emerge, although they come from a Pax7-/Myf5- origin. These adipocytes are called brite (brown-in-white) or beige, but also “inducible” since they are responsible for adaptative thermogenesis or “browning.” As an example of this adaptation capacity, if BAT is removed from mice, there is a significant “browning” process triggered in WAT as a compensatory mechanism (Piao et al. 2018).

Clinical Measurement of Brown Adipose Tissue There are currently 91 clinical trials registered in the USA that target BAT in obesity, diabetes, or cardiovascular disease. In this context, it is essential to have imaging-based tools that unequivocally identify the presence and effect of regulators on BAT activity in humans. Below, the most commonly used techniques will be described, together with some promising new approaches. We recommend as additional reading the reviews by Sampath et al. (2016) and Ong et al. (2018).

Positron Emission Tomography (PET) Imaging 18

F-fluorodeoxyglucose PET (18F-FDG PET) has been used in oncology to detect tumors, since FDG is internalized by glucose receptors and trapped intracellularly by the action of hexokinase in areas with an elevated consumption of glucose. On several occasions, the signal was detected in areas other than tumors. The combination of this result with morphological information obtained from computational tomography (CT) scans, allowed the co-localization of FDG-positive areas with a high-lipid density. In 2009, the set of independent research that triggered BAT rediscovery used 18F-FDG PET/CT to track BAT mass and activity in humans (Cypess et al. 2009; van Marken Lichtenbelt et al. 2009;

M. Alcalá et al.

Virtanen et al. 2009; Saito et al. 2009). As this technique relies on glucose uptake by active tissue, non-stimulated adult humans can sometimes be wrongly categorized as BAT-negative because of a lack of signal in the PET, when they would be better classified as BAT-inactive. In fact, cold exposure or drug-driven activation in these patients usually leads to an increase in the standardized uptake value (SUV) (Garcia et al. 2006). Although 18F-FDG PET/CT is probably the most common technique used for BAT visualization, there are several limitations to this approach. First, it requires the use of ionizing radiation and trained personal. Second, the technical protocols to measure BAT activation also differ (from temperature-controlled rooms or cooling vests to adrenergic stimulation by drugs), which leads to wide dispersion of observed effects. In this context, a panel of experts established the BARCIST recommendations to enhance comparability across experiments (Chen et al. 2016). The technique is based on glucose uptake, which is not even the preferential energy substrate in BAT and can be modified by disease (obesity, diabetes), drugs (β-blockers, anxiolytics), outer temperature or individual factors such as age, gender, or ethnicity (Soderlund et al. 2007; Pfannenberg et al. 2010; Pace et al. 2011; Rakheja et al. 2011). Consequently, the use of other molecular trackers has been proposed, although most of them rely on BAT activity. For instance, (14C)FBnTP (14C-F-fluorobenzyl triphenyl phosphonium) is used as a tracker of membrane potential, which decreases after BAT activation (Madar et al. 2011). 11C-MRB (11C-(S,S)-O-methylreboxetine) (Hwang et al. 2015) and 18F-THA (14 (R,S)-18fluoro-6-thiaheptadecanoic acid) (Ouellet et al. 2012) are used as trackers of fatty acid uptake and oxidation, and 15O-O2 detects increased mitochondrial oxygen consumption after BAT activation (Mueez et al. 2016). More recently, 11C-PBR28 (11C-peripheral benzodiazepine receptor tracker, an outer membrane protein in the mitochondria) has shown promising results, detecting BAT mass independently of its activation degree (Ran et al. 2018).

4

Brown Adipose Tissue in Obesity and Diabetes

Magnetic Resonance (MR) MR is a noninvasive technique based on the use of magnetic fields and electromagnetic radiation to detect mainly the hydrogen, carbon, or xenon nucleus. In the presence of a magnetic field, protons will align with it in two differential spin states: a stable, low-energy spin and a high-energy spin. With the application of electromagnetic radiation, low-energy nuclei suffer a transition to high-energy protons, absorbing a discrete amount of energy called precession frequency, that can be detected. This value differs in aqueous or lipid environments, allowing the detection of fat depots. The application of this technique to BAT detection has been brilliantly reviewed by Karampinos et al. (2019). Due to the lack of ionizing radiation, this technique can be safely used in infants or to establish protocols using repeated measurements, such as pre- and post-intervention studies or time-course analysis. This methodology can structurally identify BAT and even distinguish it from WAT (Hamilton et al. 2011), although MR fat fraction measurements have certain limitations as the spatial resolution is restricted to 1 mm3. For instance, it may not be possible to resolve differences between intracellular water and non-lipid structures, such as vessels or connective tissue. In addition, it is not possible to differentiate white, brown, and beige adipocytes when they coexist in the same depot, as occurs in obese patients or in the supraclavicular regions. Nevertheless, modifications in the protocol have been published that solve this issue, based on the smaller size of BAT lipid droplets (Branca and Warren 2011). In addition, MR technology can be adapted to determine BAT activity. Water-fat composition studies can be used to determine intracellular lipid extinction, used as a fuel to generate heat during cold-induced BAT activation. The increase in blood flow can be tracked using a technique known as the blood-oxygen-leveldependent (BOLD) effect, that relies on the differential paramagnetic properties of oxyhemoglobin and deoxyhemoglobin (Iris Chen et al. 2013). Other emerging but still experimental approaches

39

involve hyperpolarized MR imaging, using the lipophilic accumulation of 129Xe to measure BAT perfusion or the breakdown of hyperpolarized 13C-pyruvate into bicarbonate and lactate (Branca et al. 2014).

Preclinical Imaging Techniques (Thermometry, Ultrasound, and Near-Infrared Spectroscopy) The increase in skin temperature associated with the thermogenic activity of the BAT can be directly measured using infrared thermography (IRT). This approach is widely used in animal models in preclinical studies. In the last decade, the technique has also been applied in humans due to its simplicity, reduced cost, and safety, which allows repetitive measurements and use in sensitive populations. In humans, IRT is used to detect changes in skin temperature, although it is limited to the supraclavicular region, where BAT is more superficial. Several authors have demonstrated that cold-induced activation of BAT determined by 18F-FDG PET/CT correlates with an increase in skin temperature detected by IRT (Law et al. 2018). However, this approach has several limitations. First, it is a method based on tissue activation, which implies that inactive BAT will not be detected unless there is a change in temperature generation. Second, it currently lacks a standardized protocol in terms of patient preparation (acclimatization, cold intensity, and duration) or data analysis (image acquisition and analysis of the region of interest). Finally, but crucially, the determination of supraclavicular BAT-generated temperature can be highly limited by (i) the shielding effect of the surrounding tissues and (ii) the contribution to skin temperature of increased blood flow after BAT activation. For instance, the thickness of the subcutaneous adipose tissue in obese patients hampers the diffusion of the temperature toward the skin, misleading the signal acquisition. To our knowledge, only two reports have evaluated BAT activation using this approach in obese patients, and both of them explicitly acknowledge the

40

limitations of the protocol (El Hadi et al. 2016; Hartwig et al. 2017).

Ultrasonography Ultrasounds are based on identifying increased blood flow in activated BAT by detecting microbubbles injected into patients. This technique has obtained promising results in mice, in which norepinephrine activated BAT was detected and estimated BAT mass was obtained, that correlates with the observed results after necropsy. However, its application in humans is currently limited to a small pilot project in 13 lean patients, in whom ultrasound-detected BAT mass activation was similar to that detected by 18 F-FDG PET/CT (Flynn et al. 2015). Near-Infrared Spectroscopy (NIRTRS) NIRTRS is based on the relative transparency of tissues to near-infrared wavelengths, and the differential absorption of hemoglobin and myoglobin in relation to oxygenation state. The technique can be used to detect hemoglobin oxygenation in the microvasculature, which is inversely related to oxidative activation of BAT. However, while the first studies in humans reported comparable results in the detection of supraclavicular BAT to the gold standard 18F-FDG PET/CT (Nirengi et al. 2015), later reports noted that this technique is apparently unable to detect changes after BAT activation (Hartwig et al. 2017; Acosta et al. 2019), which would potentially limit the use of this simple, noninvasive method.

Secretory Activity of Brown Adipose Tissue The secretory profile of WAT in lean, obese, and diabetic individuals has been thoroughly studied in the past two decades (Lee et al. 2019). However, a focus on the BAT secretome has been more recent. Due to the distinct roles of both adipose depots in energy metabolism, it is not likely that the type, amount, roles in signaling pathways and targets of the molecules secreted by BAT are similar (Villarroya et al. 2019a).

M. Alcalá et al.

Brown Adipokines or “Batokines” The term “batokines” (BAT-secreted mediators or brown adipokines) refers to the proteins, peptides, metabolites, regulatory factors, or miRNAs released by brown fat tissue, including BAT-resident cells other than brown adipocytes such as immune cells, preadipocytes, neurons, etc. They can be classified according to their chemical nature, their role in the regulation of the thermogenic process (Villarroya et al. 2017a, b, 2019a), or their mechanism of action in cellular communication (autocrine, paracrine, or endocrine) (Villarroya et al. 2017b). Table 4.1 summarizes the BAT-secreted signaling molecules that have been identified in basal conditions. Using a proteomics approach, two recent studies (Ali Khan et al. 2018; Villarroya et al. 2019b) reported a set of proteins secreted after cAMP and noradrenaline stimulation of brown adipose murine cells. The studies show 60% coincidence, but interestingly both identified extracellular matrix (ECM) components (distinct types of collagens) or regulators (matricellular proteins: non-structural proteins in the ECM with a regulatory role) as members of the secretome of thermogenically activated brown adipocytes. This highlights the importance of BAT remodeling when the tissue has to be expanded in response to thermogenic activation (Villarroya et al. 2019a). In humans, a pilot study using comparative proteomics between white and brown adipocytes identified 101 proteins that are exclusively secreted by the BAT (Deshmukh et al. 2019).

Batokines and Transplantation A direct way to identify the endocrine secretion of batokines is through BAT transplantation studies. For example, BAT transplantation in animal models of type I diabetes (Gunawardana and Piston 2012, 2015) has been shown to improve glycemia. In type II diabetes (high-fat dietinduced and ob./ob mice), BAT transplantation increased energy expenditure and improved glucose tolerance (Stanford et al. 2013; Liu et al. 2013, 2015; Zhu et al. 2014). BAT

4

Brown Adipose Tissue in Obesity and Diabetes

41

Table 4.1 Secreted molecules by BAT after cold/adrenergic activation with recognized function Gene Adipoq Angptl8 Agt Bmp8b

Protein Adiponectin Angiopoietin-like protein-8 Angiotensinogen Bone morphogenetic protein-8b

Cxcl14 Edn-1 Fgf2 Fgf21 Fst Gdf15 Igf1

C-X-C motif chemokine 14 Endothelin-1 Fibroblast growth factor-2 Fibroblast growth factor-21 Follistatin Growth and differentiation factor-15 Insulin-like growth factor-1

Il6

Interleukin-6

Ptgds

Lipocalin prostaglandin D synthase

Lr11

Low-density Lipoprotein receptor relative, soluble form Meteorin-like

Metrnl Mstn Ngf Nrg4

Myostatin/growth and differentiation factor-8 Nerve growth factor Neuregulin-4

Pm20d1

Peptidase M20 domain-containing protein 1 S100b S100-B protein Slit2 C-terminal fragment of SLIT2 protein Vegfa Vascular endothelial growth factor A Non-peptidic Adenosine (9Z)-12,13-Dihydroxy-9-octadecenoic acid (12,13-diHOME) Endocannabinoids Hydrogen peroxide (H2O2) miR-99b Nitric oxide Prostaglandins Triiodothyronine

Function Thermogenesis inactivation. Thermogenesis inactivation. Enhances BAT differentiation. Enhances BAT differentiation. Increases sympathetic tone in BAT. Thermogenesis activation by M2 macrophage recruitment. Thermogenesis inactivation. Enhances BAT differentiation. Thermogenesis activation. Thermogenesis activation. Acts in immune cells to reduce inflammation. Glucose homeostasis. BAT differentiation. Glucose homeostasis. Regulation of Inflammation. BAT activation and WAT browning. Control of substrate choice in BAT (glucose vs lipids) Thermogenesis activation Thermogenesis activation through immune cells-mediated catecholamine release Thermogenesis inactivation Enhances BAT activity by increasing innervation Hepatic lipogenesis, fuel oxidation. Promotes BAT activation by increasing angiogenesis. Thermogenesis activation UCP1-independent. Enhances BAT activity by increasing innervation. Thermogenesis activation. Enhances BAT activity by increasing vascularization. Thermogenesis activation. Promotes fatty acid uptake by BAT. Thermogenesis inactivation. vasodilation and second messenger in BAT differentiation. Inhibits hepatic FGF21 expression. Vasodilation in BAT and activation of thermogenesis. BAT activation and WAT browning. Control of substrate choice in BAT (glucose vs lipids) Thermogenesis activation

transplantation can increase sympathetic tone and affect the endogenous BAT, WAT, heart, and muscle of recipient mice (Zhu et al. 2014). These effects cannot be exclusively explained by an increase in thermogenesis, so the consensus conclusion is that the BAT secretome should account for the observed phenotypical improvements.

Brown Adipose Tissue Signaling to Other Tissues There is still little evidence about the role of the BAT endocrine secretome and its effects on target organs (Fig. 4.2). Here we highlight some of the more recent and relevant findings.

42

M. Alcalá et al.

Fig. 4.2 Brown adipose tissue crosstalk. The activation of BAT stimulates the secretion of signaling molecules that target different organs, exerting regulatory roles in fatty acid oxidation and glucose uptake by the muscle, cardioprotective effects in the heart, regulation of blood

pressure and arterial stiffness in blood vessels, the promotion of an anti-inflammatory phenotype in immune cells, regulation of lipid metabolism in the liver, regulation of ovulation and participation in the regulatory mechanism of the metabolism by the central nervous system

Muscle Physical exercise is a common non-pharmacological approach to treat metabolic diseases. Besides enhancement of muscular function per se, the study of bidirectional communication between muscle and BAT is beginning to reveal new agents that regulate the beneficial effects of exercise. For instance, exercise increases WAT browning through the secretion

of myokines (Boström et al. 2012), and mildly increases BAT thermogenic activity in a lactatedriven mechanism (De Matteis et al. 2013). In the other direction, BAT seems to modify skeletal muscle function through the secretion of myostatin, which inhibits skeletal muscle cell growth and differentiation. Under thermoneutral temperature, BAT inactivation led to increased

4

Brown Adipose Tissue in Obesity and Diabetes

myostatin secretion, reducing the exercise capacity of skeletal muscle. However, BAT activation lowered myostatin levels and favored exercise performance (Kong et al. 2018). BAT also participates in fatty acid uptake and oxidation by muscle, through the secretion of 12,13dihydroxy-9Z-octadecenoic acid (12,13diHOME) after exercise (Stanford et al. 2018). Cardiovascular System Under thermogenic activation, BAT strongly releases fibroblast growth factor 21 (FGF21) (Hondares et al. 2011). Tissues and organs such as WAT, brain, pancreas, and heart are known to be sensitive to FGF21 action. In the heart, FGF21 seems to have a strong cardioprotective effect (Planavila et al. 2013) by attenuating hypertensive cardiac remodeling (Thoonen et al. 2015; Ruan et al. 2018). There is also increasing evidence of the role of BAT signaling to blood vessels. For instance, bone marrow protein 8 b (BMP8b, one of the most abundantly expressed genes after BAT activation) and vascular endothelial growth factor (VEGF-α) promote angiogenesis, which is required to increase vascular density and thermogenesis in the BAT (Bagchi et al. 2013; Pellegrinelli et al. 2018). In addition, BAT removal in lean mice caused aortic stiffness, which suggests a key contribution to vascular remodeling (Grunewald et al. 2018). Finally, several proteins and non-proteins secreted by BAT play a key role in maintaining blood pressure both by causing contraction (endothelin, some prostaglandins) and/or relaxation (adenosine, H2O2, nitric oxide). Although this indicates that BAT is an important regulator of vascular function, more research is required to understand its specific contribution. Immune Cells Polarization of the infiltrated immune cells within BAT or beige adipocytes conditions the thermogenic programming of the tissue (Villarroya et al. 2018a, b). While the recruitment of M2-alternative activated macrophages promotes BAT function, M1-pro-inflammatory

43

macrophages are negatively associated with the thermogenic activity (Villarroya et al. 2019a). In normal circumstances, stimulated brown adipocytes can decrease the inflammatory response in macrophages in a paracrine fashion (Dowal et al. 2017). The release of chemokine (C-X-C motiv) ligand 14 (CXCL14) batokine leads to the alternative activation and recruitment of M2-macrophages in response to noradrenergic stimulation (Cereijo et al. 2018), while growth and differentiation factor-15 (GDF15) exerts anti-inflammatory effects on M1-macrophages (Verdeguer et al. 2015; Campderrós et al. 2019). One of the most studied cytokines, interleukin6 (IL-6) plays a dual pro-inflammatory and antiinflammatory role. In BAT, it is secreted in response to cold and noradrenergic stimulation and it has been reported as crucial to maintain the thermogenic response. As an example, BAT transplantation from IL-6 KO mice loses the capability of promoting a healthy metabolic response in HFD-fed mice (Stanford et al. 2013). Other factors secreted by BAT exhibit pro- and anti-inflammatory functions, such as endocannabinoids, chemerin, or prostaglandins, whose endocrine role and implication in BAT crosstalk to other tissues is yet to be defined. Liver Considering that BAT activation relies mainly on glucose and fatty acid flux rather than on intracellular stored fuels, it seems reasonable that there is crosstalk between both organs, as the liver is the key regulatory organ in glucose and lipid homeostasis. FGF21 has been identified as a key molecule in this communication. In normal conditions, most circulating FGF21 is synthesized in the liver, where it participates in fatty acid oxidation and insulin sensitivity (Markan et al. 2014). To maximize fuel efflux for thermogenic activity under adrenergic or cold stimulation, BAT responds in a dual mode. First, it induces the expression of miR-99b, which, along with other miRNAs, is packed in exosomes and travels to the liver, where it inhibits FGF21 expression (Thomou et al. 2017) to minimize fuel consumption by the liver.

44

The second effect is the induction of BAT FGF21 expression, which will act in an autocrine fashion enhancing triglyceride-rich lipoprotein uptake and oxidation (Hondares et al. 2011; Schlein et al. 2016). Another batokine, neuregulin 4 (Nrg4) reduces steatosis by controlling de novo lipogenesis in the liver. It may be a useful strategy to treat non-alcoholic fatty liver disease, as Nrg4 levels are downregulated in obesity (Wang et al. 2014). In a similar manner, adiponectin secreted by the BAT may reduce hepatocyte damage and death in alcohol-induced steatosis (Shen et al. 2019). Female Reproductive Tract In ovariectomized mice, the development of obesity appears to be partially mediated by loss of BAT activity (Bartness and Wade 1984; Pedersen et al. 2001), probably related to the estrogen receptor present in BAT (Wade and Gray 1978). Women with polycystic ovary syndrome report lower BAT activity (Flávia et al. 2019), whereas transplantation of BAT in rats reversed polycystic ovaries and hyperandrogenism, and reduced infertility by reversing anovulation (Yuan et al. 2016). Whether this improvement is related to the thermogenic activity or the secretory role of BAT is still to be determined. Brain Some of the autocrine/paracrine factors released by BAT act in the brain to activate neural circuits that innervate adipose tissues and cooperatively regulate lipid metabolism and energy homeostasis. One of these well-defined adiposederived secretory factors is leptin. The expression of this gene is similar in WAT and BAT in lean mice, but WAT expresses significantly greater levels than BAT in obese mice. Leptin acts through leptin receptor (LepRb) to enhance the excitability of neurons of different parts of the brain including the arcuate nucleus (ARC), dorsomedial hypothalamic nucleus (DMH), median preoptic subnucleus (MnPO) and the nucleus of the solitary tract (NTS), implicated in the regulation of BAT (Zhang et al. 2011). The ARC nucleus in the hypothalamus is in contact with the blood-brain barrier and is

M. Alcalá et al.

considered one of the gates for the brain to sense circulating factors. Leptin action in ARC increased thermogenesis in BAT by activating the efferent sympathetic nervous system (SNS) (Rahmouni and Morgan 2007; Harlan et al. 2011), through the induction of anorexigenic neuropeptide precursor proopiomelanocortin (POMC) expression and increasing the release of POMC products in second-order neurons (Yasuda et al. 2004; Dodd et al. 2015). Another population of ARC neurons, the GABAergic RIP-Cre (Cre-mediated expression of rat insulin II promoter) are also activated by leptin and are involved in the neural circuits that activate BAT thermogenesis (Kong et al. 2012). Mice fed with a high-fat diet had impaired BAT sympathetic neuronal activation in response to systemic leptin, but the leptin intraparenchymal injection in diet-induced obese (DIO) mice increased BAT temperature (Enriori et al. 2011). Other batokines such as FGF21 (Mutsnaini et al. 2019) and Ngr4 (Rosell et al. 2014) interact with neural circuits to modulate BAT activity and cooperatively regulate whole-body energy metabolism. Systemic Influences Other hormonal and nutritional signals and stimuli (temperature, immunologic responses, stress, and hypoxia) may have neurochemical influences on the central nervous system (CNS) networks that govern BAT sympathetic nerve activity. They may drive sympathetic BAT activation or inhibition and control BAT thermogenesis and energy expenditure, and contribute to whole-body energy homeostasis (see reviews by Morrison et al. 2014; Contreras et al. 2017).

Neuroendocrine Regulation of Brown Adipose Tissue The central nervous system (CNS) integrates a wide array of environmental stimuli: diet, fasting, exercise, temperature, and behavioral states, sending outward neural signals via the autonomic nervous system that directly contact multiple

4

Brown Adipose Tissue in Obesity and Diabetes

tissues to control metabolism and energy balance. Crosstalk between adipose tissues (BAT and different WATs) and CNS has emerged as an important issue for maintaining energy balance and promoting survival in response to metabolic challenges such as obesity. Therefore, intense research is focused on understanding the bidirectional communication between fad pads and brain. This encompasses endocrine signals from adipose tissues to CNS and neural signals through efferent sympathetic nerves and afferent sensory nerves and provides a framework for understanding overall BAT thermogenesis by the CNS (recently reviewed in François et al. 2018; Blaszkiewicz et al. 2019; Zhu et al. 2019).

Sympathetic BAT Innervation The sympathetic innervation of BAT was described nearly a century ago. The physiological effect of sympathetic stimulation of neurons that innervate BAT is increased thermogenesis. The secretion of norepinephrine at the terminal nerves that surround adipocytes activates β3-adrenergic receptor and the signaling pathways that promote lipolysis, fatty acid (FA) oxidation, UCP1 protein expression and heat dissipation of the energy of FA (Cannon and Nedergaard 2004; Contreras et al. 2017). Several technologies have been used to demonstrate sympathetic innervation of BAT. Bartness and colleagues have provided important histological and functional evidence of brain sympathetic neuronal connectivity with adipose tissues by using pseudorabies virus (PRV), a retrograde trans-synaptic neuronal tracer that only traces sympathetic neurons that are synaptically connected. They showed the hierarchical neuronal pathways defining pre- and postganglionic sympathetic innervation of BAT (Bamshad et al. 1999; Song et al. 2008) in Siberian hamsters and rats, and the description of a higher order of neurons located in different parts of the brain such as the hypothalamus and raphe pallidus (Bamshad et al. 1999; Oldfield et al. 2002; Cano et al. 2003). In addition, immunohistochemical labeling with tyrosine hydroxylase (TH), a

45

specific marker for sympathetic nerve fibers involved in the biosynthesis of norepinephrine, have shown dense innervation of BAT (Giordano et al. 1996; Murano et al. 2009). Under cold exposure, it has been shown that TH increases at BAT parenchymal nerve fibers with a concomitant increase of UCP1 expression, which indicates enhanced sympathetic and thermogenic activity (Brito et al. 2008; Murano et al. 2009).

Experimental Denervation Other techniques such as surgical or chemical denervation of BAT decreased UCP1 expression and highlighted the functional relevance of BAT innervation in regulating thermogenesis, energy expenditure, body mass, and browning (Dulloo and Miller 1984; Klingenspor et al. 1994; Nguyen et al. 2017). In addition, BAT sympathetic denervation can activate the sympathetic activity of other adipose tissues. For example, it can promote browning in inguinal WAT and suggests tissue crosstalk with the brain to modulate energy balance (Nguyen et al. 2017). Diet can modulate the sympathetic activity of BAT. Acute HFD treatments increase the norepinephrine (NE) turnover in BAT but this decreases after long treatments with HFD (Levin et al. 1983). More recently, it has been shown that dietinduced obesity increases UCP1 protein in mice and rats (Fromme and Klingenspor 2011; Alcalá et al. 2017) and BAT temperature after 20 weeks of diet (Enriori et al. 2011), which suggests that sympathetic activity in BAT increases to promote energy expenditure in conditions of excess calories.

Sensory Innervation of BAT The first studies that suggest the presence of sensory neurons in BAT were performed by immunohistochemical detection of sensory nerve associated markers, such as calcitonin generelated peptide (CGRP) and substance P (Giordano et al. 1996). More recent studies with anterograde transneuronal tracer have confirmed the presence of sensory nerve projections from BAT to dorsal root ganglia, which propagate their

46

signal to the CNS (Bartness et al. 2010; Ryu et al. 2015). In addition, it has been demonstrated that there is considerable crosstalk between adipose tissues and the CNS. BAT and WAT can share some sympathetic outflows from the CNS, and sensory information circuits of BAT and sympathetic circuits of WAT and vice versa have important overlaps in the CNS (Nguyen et al. 2017; Ryu et al. 2017). In addition, it has been shown that sensory information about activated lipolysis in WAT can influence the efferent CNS circuits to BAT, by activating thermogenesis in this tissue (Garretson et al. 2016). All these data suggest a feedback mechanism that sensory information from each adipose tissue is communicated to the brain by an afferent pathway, which integrates the signal and regulates the efferent sympathetic outputs to each specific adipose tissue. Nevertheless, the nature of the signals that activate sensory neurons in different adipose tissues is unknown. Only a few brown adipokines (nerve growth factor [NGF], NRG4) have been identified as an outgrowth of promoters of sympathetic neurites (Néchad et al. 1994; Murano et al. 2009).

Adipose Tissue Dysfunction in Obesity and Diabetes Since the mid-1990s, WAT has been seen not just as a storage depot, but also as an active, secretory tissue that establishes crosstalk with other organs. Dysregulation in this communication is a typical feature in obesity and diabetes and is partly responsible for adverse metabolic outcomes in organs such as muscle, liver, and blood vessels.

Sick Fat WAT malfunction in obesity is characterized by the following anatomical and functional processes: – Structural changes in the size (hypertrophy) and number (hyperplasia) of adipocytes and stiffness of the extracellular matrix

M. Alcalá et al.

– Infiltration of immune cells, together with increased inflammatory secretion – Oxidative and endoplasmic reticulum stress – Defective lipolysis and increased energy metabolism – Insulin resistance – Mitochondrial dysfunction These processes are not isolated events, but they are interconnected. For instance, oxidative stress increases endoplasmic reticulum stress, promotes inflammation, and participates in insulin resistance.

The WAT Expandability Hypothesis The WAT expandability hypothesis tries to establish a time-course description of the events that begin with the increased demand for triglyceride storage (Tan and Vidal-Puig 2008). This hypothesis claims that there is an individual limit for fat accumulation within WAT. As long as this limit is not exceeded, the expansion of WAT will be healthy, which explains the presence of approximately 20% of morbidly obese patients who do not exhibit the expected comorbidities (dyslipidemia, type 2 diabetes or hypertension). However, if the limit is surpassed, fat accumulation begins in ectopic tissues, leading for example to fatty liver or cirrhosis or loss of insulin sensitivity in the muscle. In this unhealthy expansion model, the extracellular matrix is remodeled and becomes fibrotic, impeding the hypertrophy of adipocytes, which get isolated from oxygen and food supply from blood vessels. As a response, the recruitment of immune cells begins through adipokine secretion, with a triple mission: (i) to attract blood monocytes to the tissue, which will become pro-inflammatory macrophages to phagocyte the apoptotic adipocytes; (ii) to generate new blood vessels to maximize oxygen and food supply to the hypertrophic adipocytes, whose size can become bigger than the oxygen diffusion limit (~100 μm) and (iii) to reduce insulin sensitivity, in order to limit the accumulation of triglycerides mediated by the insulin lipogenic effect. However, when obesity

4

Brown Adipose Tissue in Obesity and Diabetes

becomes chronic, these changes in the biology of the adipocyte are not self-controlled, and the secretory profile of WAT negatively affects other tissues (Sun et al. 2011).

Brown Adipose Tissue in Obesity and Diabetes In spite of the technical problems when it comes to measuring BAT amount and activity with current imaging methods, particularly in obese or type 2 diabetic patients, it is well-established that both the basal activity and its response to stimuli (cold, adrenergic agonists) is considerably diminished in these patients (Cypess et al. 2009; Eriksson et al. 2019).

BAT Dysfunction During Obesity Recent studies in animal models have demonstrated that BAT from obese individuals undergoes similar pathological processes during obesity development, such as changes in the extracellular matrix, infiltration of immune cells and pro-inflammatory secretion, oxidative stress and changes in energy metabolism. Nonetheless, in comparison to WAT, the appearance of these processes is delayed since WAT preferentially uptakes the circulating fat (McGregor et al. 2013; Alcalá et al. 2017). However, once fat begins to accumulate within the brown adipocyte, a clear change in the phenotype is observed (commonly known as “whitening”). The change is characterized by an increase in the size of the multilocular lipid droplets, which gives the adipocyte a “white” appearance that is translated into a loss of thermogenic potential. Reduced adrenergic stimulation, the role of adipokines/batokines, oxidative and endoplasmic reticulum stress, and some miRNAs are potentially responsible for the obesity-related decrease in BAT mass (Alcalá et al. 2019). Infiltration of activated M1 macrophages and pro-inflammatory cytokines promote a decline in UCP1 expression, which alters thermogenic activity (Sakamoto et al. 2016; Villarroya et al. 2018a). Oxidative stress is also responsible for BAT activity decline (Cui et al. 2019) (Fig. 4.3).

47

Therapeutic Perspectives for Brown and White Adipose Tissue Manipulation As one of the regulators of body temperature, BAT controls triglyceride levels and uses glucose and lipids to fuel thermogenesis to produce heat. Therefore, the process of thermogenesis is associated with several metabolic pathways such as mitochondrial respiration, lipolysis, lipogenesis, or FA uptake, transport, storage, and oxidation (Calderon-Dominguez et al. 2016). In experimental animals, activated BAT is the major plasma lipid-clearing organ and has the highest FA oxidation rate (Doh et al. 2005; Bartelt et al. 2011). The fact that aging, obesity, and diabetes have been associated with a decrease in the presence and activity of BAT in humans has highlighted BAT as a potential therapeutic target for metabolic diseases (Hany et al. 2002; Nedergaard et al. 2007; Cypess et al. 2009; Zingaretti et al. 2009; van Marken Lichtenbelt et al. 2009; Virtanen et al. 2009; Saito et al. 2009). These studies indicated that, in addition to its role in coldinduced thermogenesis, BAT also plays a key role in diet-induced thermogenesis. Efforts to enhance either the activity or the mass of thermogenic adipocytes include the increase in brown adipocyte differentiation or de novo brown adipogenesis, the transdifferentiation of white into beige and thermogenic adipocytes, boosting BAT activity, and the transplantation of thermogenic adipocytes.

Chemical Activation of BAT In addition to natural activators of thermogenesis such as cold or exercise, several other activators have been described, such as bone morphogenetic protein 7 (BMP7) (Tseng et al. 2008; Boon et al. 2013) and BMP8b (Whittle et al. 2012), irisin (Boström et al. 2012), natriuretic peptides (Bordicchia et al. 2012), norepinephrine (Villarroya and Vidal-Puig 2013), meteorin-like (Rao et al. 2014), bile acids (Watanabe et al. 2006), adenosine (Gnad et al. 2014), FGF21

48

M. Alcalá et al.

Fig. 4.3 Effects of obesity and diabetes in the development and function of adipose tissue. The pathological mechanisms that characterize obesity and diabetes can disturb the differentiation of brown adipocytes from precursor cells. They can also interfere in transdifferentiation

processes, initially by promoting browning of white adipocytes to overcome the excess of nutrients and finally shifting the phenotype of brown adipocytes toward a white adipocyte (whitening). The thermogenic activation of BAT is also interrupted

(Hondares et al. 2010), or the β3-adrenergic receptor agonist mirabegron (Cypess et al. 2015). These factors have been shown to boost the browning of adipose tissue, i.e., increased expression and activity of UCP1 within WAT, and have been extensively reviewed (Bonet et al. 2013; Wu et al. 2013; Calderon-Dominguez et al. 2016).

Bat Transplantation The potential benefits of transplanting functional BAT are currently under study in animal models (Soler-Vázquez et al. 2018; White et al. 2019). In the case of adipocyte implantation, adipocytes could be obtained from mesenchymal stem cells (MSCs). MSC sources include embryonic stem

4

Brown Adipose Tissue in Obesity and Diabetes

cells, and stem cells isolated from bone marrow, umbilical cord, peripheral blood, adipose tissue, bone marrow, cartilage, tendon, muscle, and dental pulp. Adipose tissue derived-MSCs (Ad-MSCs) are currently predominant in the study of metabolic diseases since a large number of MSCs can be isolated, and because they have a higher capacity to differentiate into mature adipocytes (Rashnonejad et al. 2018). Lee et al. injected human MSC-derived brown adipocytes intraperitoneally into obese mice for 10 weeks (Lee et al. 2017). This treatment successfully decreased bodyweight, triglyceride and cholesterol levels, hepatic steatosis, glucose intolerance, and inflammation. Silva et al. found a reduction in body weight and glucose levels in non-obese diabetic (NOD) mice fed an HFD, that had been transplanted with differentiated Ad-MSCs isolated from human mediastinal brown fat depots (Silva et al. 2014). Improvements in glucose and lipid homeostasis have also been described in obese and diabetic mice subcutaneously transplanted with brown adipocytes, generated by cellular reprogramming procedures using induced pluripotent stem cells (iPSC) or from mouse embryonic fibroblasts (Kishida et al. 2015). Another example of the successful effects of adipocyte implantation on metabolic phenotype is an elegant study by Min et al. (2016). Beige adipocytes were derived from human capillary network progenitors and activated in vitro with adrenergic stimuli. The subcutaneous implantation of these thermogenic adipocytes into NOD mice treated with HFD led to an improvement in systemic glucose tolerance.

Direct BAT Grafting Several studies have performed direct BAT transplantation in mouse models of diabetes and/or obesity (Gunawardana and Piston 2012, 2015; Stanford et al. 2013, 2015; Liu et al. 2013, 2015; Zhu et al. 2014). Regardless of the BAT donor (embryonic or adult), the location of the transplantation (subcutaneous or the visceral cavity), or the type of transplanted fat (exerciseinduced beige fat or BAT), these studies showed

49

a reduction in glucose and insulin levels, adiposity, inflammation, hepatic steatosis and an increase in oxygen consumption. Finally, BAT transplantation has shown metabolic improvements in other derangements such as Parkinson’s disease (Wu et al. 2017), cardiovascular disease (Thoonen et al. 2015), polycystic ovary syndrome (Yuan et al. 2016) and atherosclerosis (Kikai et al. 2017).

Promises and Pitfalls of Human BAT Transplantation First, in humans, there might be differences in the MSCs source, isolation method, duration, and capacity for differentiation to mature adipocytes, and the obtained outcomes. Second, due to its body distribution, adipose tissue in humans might be less accessible than in rodents. Ad-MSCs can be isolated from WAT during elective surgical interventions such as liposuction. Third, the beneficial effects of BAT transplantation might include several mechanisms, such as the endocrine release of batokines that should be further investigated. Fourth, most of the transplantation experiments have been performed with mice housed under thermal stress (22  C), in order to activate BAT. Cannon and colleagues correctly claim that if animal experiments are to be translated into humans, mice should be housed at thermoneutrality (30  C for mice; 22  C for humans) since humans usually live at thermoneutrality throughout the year (Fischer et al. 2019). As thermogenesis is tightly adjusted to ambient temperature, it is not known whether BAT thermogenesis might reach a threshold. Thus, the effectiveness might be questionable if the individual is at thermoneutrality. Finally, BAT activation could be associated with excessive body temperature, or perhaps enhanced food intake as a compensatory effect to normalize energy balance. Clinical administration of the BAT-stimulating β3-adrenergic receptor agonist Mirabegron to young lean males was associated with increased glucose uptake into BAT, elevated resting metabolic rate, and tachycardia (Cypess

50

et al. 2015), even though the protocol is criticized because the dosage was atypically high. Thus, the search for potential therapies that aim to increase BAT mass or activity at thermoneutrality to fight against obesity and its associated metabolic diseases should continue. Acknowledgments This study was supported by the Ministry of Spain (MINECO) (SAF2017-83813-C3-1-R to DS and LH, cofounded by the ERDF), the Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y la Nutrición (CIBEROBN) (Grant CB06/03/ 0001 to DS), the Government of Catalonia (2017SGR278 to DS), the Universidad CEU San Pablo-Banco Santander (FUSP-BS-PPC-USP02/2017) to MA and the Fundació La Marató de TV3 (201627-30 to DS).

References Acosta FM, Berchem J, Martinez-Tellez B et al (2019) Near-infrared spatially resolved spectroscopy as an indirect technique to assess brown adipose tissue in young women. Mol Imaging Biol 21:328–338 Alcalá M, Calderon-Dominguez M, Bustos E et al (2017) Increased inflammation, oxidative stress and mitochondrial respiration in brown adipose tissue from obese mice. Sci Rep 7:16082 Alcalá M, Calderon-Dominguez M, Serra D et al (2019) Mechanisms of impaired brown adipose tissue recruitment in obesity. Front Physiol 10:94 Ali Khan A, Hansson J, Weber P et al (2018) Comparative secretome analyses of primary murine white and brown adipocytes reveal novel adipokines. Mol Cell Proteomics 17:2358–2370 Bagchi M, Kim LA, Boucher J et al (2013) Vascular endothelial growth factor is important for brown adipose tissue development and maintenance. FASEB J 27:3257–3271 Bamshad M, Song CK, Bartness TJ (1999) CNS origins of the sympathetic nervous system outflow to brown adipose tissue. Am J Physiol 276:R1569–R1578 Bartelt A, Bruns OT, Reimer R et al (2011) Brown adipose tissue activity controls triglyceride clearance. Nat Med 17:200–206 Bartness TJ, Wade GN (1984) Effects of interscapular brown adipose tissue denervation on body weight and energy metabolism in ovariectomized and estradioltreated rats. Behav Neurosci 98:674–685 Bartness TJ, Vaughan CH, Song CK (2010) Sympathetic and sensory innervation of brown adipose tissue. Int J Obes 34:S36–S42 Blaszkiewicz M, Willows JW, Johnson CP, Townsend KL (2019) The importance of peripheral nerves in adipose tissue for the regulation of energy balance. Biology (Basel) 8:10

M. Alcalá et al. Bonet ML, Oliver P, Palou A (2013) Pharmacological and nutritional agents promoting browning of white adipose tissue. Biochim Biophys Acta - Mol Cell Biol Lipids 1831:969–985 Boon MR, van den Berg SAA, Wang Y et al (2013) BMP7 activates brown adipose tissue and reduces dietinduced obesity only at subthermoneutrality. PLoS One 8:e74083 Bordicchia M, Liu D, Amri EZ et al (2012) Cardiac natriuretic peptides act via p38 MAPK to induce the brown fat thermogenic program in mouse and human adipocytes. J Clin Invest 122:1022–1036 Boström P, Wu J, Jedrychowski MP et al (2012) A PGC1alpha-dependent myokine that drives brown-fat-like development of white fat and thermogenesis. Nature 481:463–468 Branca RT, Warren WS (2011) In vivo brown adipose tissue detection and characterization using water-lipid intermolecular zero-quantum coherences. Magn Reson Med 65:313–319 Branca RT, He T, Zhang L et al (2014) Detection of brown adipose tissue and thermogenic activity in mice by hyperpolarized xenon MRI. Proc Natl Acad Sci USA 111:18001–18006 Brito NA, Brito MN, Bartness TJ (2008) Differential sympathetic drive to adipose tissues after food deprivation, cold exposure or glucoprivation. Am J Physiol Integr Comp Physiol 294:R1445–R1452 Calderon-Dominguez M, Mir JF, Fucho R et al (2016) Fatty acid metabolism and the basis of brown adipose tissue function. Adipocyte 5:98–118 Campderrós L, Moure R, Cairó M et al (2019) Brown adipocytes secrete GDF15 in response to thermogenic activation. Obesity 27:1606–1616 Cannon B, Nedergaard J (2004) Brown adipose tissue: function and physiological significance. Physiol Rev 84:277–359 Cano G, Passerin AM, Schiltz JC et al (2003) Anatomical substrates for the central control of sympathetic outflow to interscapular adipose tissue during cold exposure. J Comp Neurol 460:303–326 Cereijo R, Gavaldà-Navarro A, Cairó M et al (2018) CXCL14, a brown adipokine that mediates brownfat-to-macrophage communication in thermogenic adaptation. Cell Metab 28:750–763.e6 Chen KY, Cypess AM, Laughlin MR et al (2016) Brown adipose reporting criteria in imaging studies (BARCIST 1.0): recommendations for standardized FDG-PET/CT experiments in humans. Cell Metab 24:210–222 Contreras C, Nogueiras R, Diéguez C et al (2017) Traveling from the hypothalamus to the adipose tissue: the thermogenic pathway. Redox Biol 12:854–863 Cui X, Xiao W, You L et al (2019) Age-induced oxidative stress impairs adipogenesis and thermogenesis in brown fat. FEBS J 286:2753–2768 Cypess AM, Lehman S, Williams G et al (2009) Identification and importance of brown adipose tissue in adult humans. N Engl J Med 360:1509–1517

4

Brown Adipose Tissue in Obesity and Diabetes

Cypess AM, Weiner LS, Roberts-Toler C et al (2015) Activation of human brown adipose tissue by a β3adrenergic receptor agonist. Cell Metab 21:33–38 De Matteis R, Lucertini F, Guescini M et al (2013) Exercise as a new physiological stimulus for brown adipose tissue activity. Nutr Metab Cardiovasc Dis 23:582–590 Deshmukh AS, Peijs L, Beaudry JL et al (2019) Proteomics-based comparative mapping of the secretomes of human Brown and White adipocytes reveals EPDR1 as a novel batokine. Cell Metab 30:963–975.e7 Dodd GT, Decherf S, Loh K et al (2015) Leptin and insulin act on POMC neurons to promote the browning of white fat. Cell 160:88–104 Doh K-O, Kim Y-W, Park S-Y et al (2005) Interrelation between long-chain fatty acid oxidation rate and carnitine palmitoyltransferase 1 activity with different isoforms in rat tissues. Life Sci 77:435–443 Dowal L, Parameswaran P, Phat S et al (2017) Intrinsic properties of brown and white adipocytes have differential effects on macrophage inflammatory responses. Mediators Inflamm 2017:1–11 Dulloo AG, Miller DS (1984) Energy balance following sympathetic denervation of brown adipose tissue. Can J Physiol Pharmacol 62:235–240 El Hadi H, Frascati A, Granzotto M et al (2016) Infrared thermography for indirect assessment of activation of brown adipose tissue in lean and obese male subjects. Physiol Meas 37:N118–N128 Enriori PJ, Sinnayah P, Simonds SE et al (2011) Leptin action in the dorsomedial hypothalamus increases sympathetic tone to brown adipose tissue in spite of systemic leptin resistance. J Neurosci 31:12189–12197 Eriksson O, Selvaraju RK, Berglund M, Espes D (2019) Metabolically active brown adipose tissue is found in adult subjects with type 1 diabetes. Int J Mol Sci 20:5827 Fischer AW, Cannon B, Nedergaard J (2019) The answer to the question “What is the best housing temperature to translate mouse experiments to humans?” is: thermoneutrality. Mol Metab 26:1–3 Flávia RO, Mamede M, Bizzi MF et al (2019) Brown adipose tissue activity is reduced in women with polycystic ovary syndrome. Eur J Endocrinol 181:473–480 Flynn A, Li Q, Panagia M et al (2015) Contrast-enhanced ultrasound: a novel noninvasive, nonionizing method for the detection of brown adipose tissue in humans. J Am Soc Echocardiogr 28:1247–1254 François M, Qualls-Creekmore E, Berthoud H-R et al (2018) Genetics-based manipulation of adipose tissue sympathetic innervation. Physiol Behav 190:21–27 Fromme T, Klingenspor M (2011) Uncoupling protein 1 expression and high-fat diets. Am J Physiol Integr Comp Physiol 300:R1–R8 Garcia CA, Van Nostrand D, Atkins F et al (2006) Reduction of brown fat 2-deoxy-2-[F-18]fluoro-D-glucose uptake by controlling environmental temperature prior to positron emission tomography scan. Mol Imaging Biol 8:24–29

51 Garretson JT, Szymanski LA, Schwartz GJ et al (2016) Lipolysis sensation by white fat afferent nerves triggers brown fat thermogenesis. Mol Metab 5:626–634 Giordano A, Morroni M, Santone G et al (1996) Tyrosine hydroxylase, neuropeptide Y, substance P, calcitonin gene-related peptide and vasoactive intestinal peptide in nerves of rat periovarian adipose tissue: an immunohistochemical and ultrastructural investigation. J Neurocytol 25:125–136 Gnad T, Scheibler S, Von Kugelgen I et al (2014) Adenosine activates brown adipose tissue and recruits beige adipocytes via A2A receptors. Nature 516:395–399 Grunewald ZI, Winn NC, Gastecki ML et al (2018) Removal of interscapular brown adipose tissue increases aortic stiffness despite normal systemic glucose metabolism in mice. Am J Physiol Regul Integr Comp Physiol 314:R584–R597 Gunawardana SC, Piston DW (2012) Reversal of type 1 diabetes in mice by brown adipose tissue transplant. Diabetes 61:674–682 Gunawardana SC, Piston DW (2015) Insulin-independent reversal of type 1 diabetes in nonobese diabetic mice with brown adipose tissue transplant. Am J Physiol Metab 308:E1043–E1055 Hamilton G, Smith DL Jr, Bydder M et al (2011) MR properties of brown and white adipose tissues. J Magn Reson Imaging 34:468–473 Hany TF, Gharehpapagh E, Kamel EM et al (2002) Brown adipose tissue: a factor to consider in symmetrical tracer uptake in the neck and upper chest region. Eur J Nucl Med 29:1393–1398 Harlan SM, Morgan DA, Agassandian K et al (2011) Ablation of the leptin receptor in the hypothalamic arcuate nucleus abrogates leptin-induced sympathetic activation. Circ Res 108:808–812 Hartwig V, Guiducci L, Marinelli M et al (2017) Multimodal imaging for the detection of brown adipose tissue activation in women: a pilot study using NIRS and infrared thermography. J Heal Eng 2017:5986452 Hondares E, Rosell M, Gonzalez FJ et al (2010) Hepatic FGF21 expression is induced at birth via PPARα in response to milk intake and contributes to thermogenic activation of neonatal brown fat. Cell Metab 11:206–212 Hondares E, Iglesias R, Giralt A et al (2011) Thermogenic activation induces FGF21 expression and release in brown adipose tissue. J Biol Chem 286:12983–12990 Hwang JJ, Yeckel CW, Gallezot JD et al (2015) Imaging human brown adipose tissue under room temperature conditions with (11)C-MRB, a selective norepinephrine transporter PET ligand. Metabolism 64:747–755 Iris Chen Y-C, Cypess AM, Chen Y-C et al (2013) Measurement of human brown adipose tissue volume and activity using anatomic MR imaging and functional MR imaging. J Nucl Med 54:1584–1587 Karampinos DC, Weidlich D, Wu M et al (2019) Techniques and applications of magnetic resonance imaging for studying brown adipose tissue morphometry and function. Handb Exp Pharmacol 251:299–324

52 Kikai M, Yamada H, Wakana N et al (2017) Transplantation of brown adipose tissue inhibits atherosclerosis in apoE-/- mice: contribution of the activated FGF-21adiponectin axis. Cardiovasc Res. https://doi.org/10. 1093/cvr/cvx212 Kishida T, Ejima A, Yamamoto K et al (2015) Reprogrammed functional brown adipocytes ameliorate insulin resistance and dyslipidemia in diet-induced obesity and type 2 diabetes. Stem Cell Rep 5:569–581 Klingenspor M, Meywirth A, Stöhr S, Heldmaier G (1994) Effect of unilateral surgical denervation of brown adipose tissue on uncoupling protein mRNA level and cytochrom-c-oxidase activity in the Djungarian hamster. J Comp Physiol B 163:664–670 Kong D, Tong Q, Ye C et al (2012) GABAergic RIP-Cre neurons in the arcuate nucleus selectively regulate energy expenditure. Cell 151:645–657 Kong X, Yao T, Zhou P et al (2018) Brown adipose tissue controls skeletal muscle function via the secretion of myostatin. Cell Metab 28:631–643.e3 Law J, Morris DE, Izzi-Engbeaya C et al (2018) Thermal imaging is a noninvasive alternative to PET/CT for measurement of brown adipose tissue activity in humans. J Nucl Med 59:516–522 Lee C-W, Hsiao W-T, Lee OK-S (2017) Mesenchymal stromal cell-based therapies reduce obesity and metabolic syndromes induced by a high-fat diet. Transl Res 182:61–74.e8 Lee M-W, Lee M, Oh K-J (2019) Adipose tissue-derived signatures for obesity and type 2 diabetes: adipokines, batokines and microRNAs. J Clin Med 8:854 Levin BE, Triscari J, Sullivan AC (1983) Altered sympathetic activity during development of diet-induced obesity in rat. Am J Physiol Regul Integr Comp Physiol 13:R347–R355 Liu X, Zheng Z, Zhu X et al (2013) Brown adipose tissue transplantation improves whole-body energy metabolism. Cell Res 23:851–854 Liu X, Wang S, You Y et al (2015) Brown adipose tissue transplantation reverses obesity in Ob/Ob mice. Endocrinology 156:2461–2469 Madar I, Isoda T, Finley P et al (2011) 18F-fluorobenzyl triphenyl phosphonium: a noninvasive sensor of brown adipose tissue thermogenesis. J Nucl Med 52:808–814 Markan KR, Naber MC, Ameka MK et al (2014) Circulating FGF21 is liver derived and enhances glucose uptake during refeeding and overfeeding. Diabetes 63:4057–4063 McGregor RA, Kwon E-Y, Shin S-K et al (2013) Timecourse microarrays reveal modulation of developmental, lipid metabolism and immune gene networks in intrascapular brown adipose tissue during the development of diet-induced obesity. Int J Obes 37:1524–1531 Min SY, Kady J, Nam M et al (2016) Human “brite/beige” adipocytes develop from capillary networks, and their implantation improves metabolic homeostasis in mice. Nat Med 22:312–318 Morrison SF, Madden CJ, Tupone D (2014) Central neural regulation of brown adipose tissue thermogenesis and energy expenditure. Cell Metab 19:741–756

M. Alcalá et al. Mueez UD, Raiko J, Saari T et al (2016) Human brown adipose tissue [(15)O]O2 PET imaging in the presence and absence of cold stimulus. Eur J Nucl Med Mol Imaging 43:1878–1886 Murano I, Barbatelli G, Giordano A, Cinti S (2009) Noradrenergic parenchymal nerve fiber branching after cold acclimatisation correlates with brown adipocyte density in mouse adipose organ. J Anat 214:171–178 Mutsnaini L, Kim C-S, Kim J et al (2019) Fibroblast growth factor 21 deficiency aggravates obesityinduced hypothalamic inflammation and impairs thermogenic response. Inflamm Res 68:351–358 Néchad M, Ruka E, Thibault J (1994) Production of nerve growth factor by brown fat in culture: relation with the in vivo developmental stage of the tissue. Comp Biochem Physiol Comp Physiol 107:381–388 Nedergaard J, Bengtsson T, Cannon B (2007) Unexpected evidence for active brown adipose tissue in adult humans. Am J Physiol Endocrinol Metab 293:E444– E452 Nguyen NLT, Barr CL, Ryu V et al (2017) Separate and shared sympathetic outflow to white and brown fat coordinately regulates thermoregulation and beige adipocyte recruitment. Am J Physiol Regul Integr Comp Physiol 312:R132–R145 Nirengi S, Yoneshiro T, Sugie H et al (2015) Human brown adipose tissue assessed by simple, noninvasive near-infrared time-resolved spectroscopy. Obes (Silver Spring) 23:973–980 Oldfield B, Giles M, Watson A et al (2002) The neurochemical characterisation of hypothalamic pathways projecting polysynaptically to brown adipose tissue in the rat. Neuroscience 110:515–526 Ong FJ, Ahmed BA, Oreskovich SM et al (2018) Recent advances in the detection of brown adipose tissue in adult humans: a review. Clin Sci 132:1039–1054 Ouellet V, Labbé SM, Blondin DP et al (2012) Brown adipose tissue oxidative metabolism contributes to energy expenditure during acute cold exposure in humans. J Clin Invest 122:545–552 Pace L, Nicolai E, D’Amico D et al (2011) Determinants of physiologic 18F-FDG uptake in brown adipose tissue in sequential PET/CT examinations. Mol Imaging Biol 13:1029–1035 Pedersen SB, Bruun JM, Kristensen K, Richelsen B (2001) Regulation of UCP1, UCP2, and UCP3 mRNA expression in brown adipose tissue, white adipose tissue, and skeletal muscle in rats by estrogen. Biochem Biophys Res Commun 288:191–197 Pellegrinelli V, Peirce VJ, Howard L et al (2018) Adipocyte-secreted BMP8b mediates adrenergicinduced remodeling of the neuro-vascular network in adipose tissue. Nat Commun 9:4974 Pfannenberg C, Werner MK, Ripkens S et al (2010) Impact of age on the relationships of brown adipose tissue with sex and adiposity in humans. Diabetes 59:1789–1793 Piao Z, Zhai B, Jiang X et al (2018) Reduced adiposity by compensatory WAT browning upon iBAT removal in mice. Biochem Biophys Res Commun 501:807–813

4

Brown Adipose Tissue in Obesity and Diabetes

Planavila A, Redondo I, Hondares E et al (2013) Fibroblast growth factor 21 protects against cardiac hypertrophy in mice. Nat Commun 4:2019 Rahmouni K, Morgan DA (2007) Hypothalamic arcuate nucleus mediates the sympathetic and arterial pressure responses to leptin. Hypertension 49:647–652 Rakheja R, Ciarallo A, Alabed YZ, Hickeson M (2011) Intravenous administration of diazepam significantly reduces brown fat activity on 18F-FDG PET/CT. Am J Nucl Med Mol Imaging 1:29–35 Ran C, Albrecht DS, Bredella MA et al (2018) PET imaging of human brown adipose tissue with the TSPO tracer [(11)C]PBR28. Mol Imaging Biol 20:188–193 Rao RR, Long JZ, White JP et al (2014) Meteorin-like is a hormone that regulates immune-adipose interactions to increase beige fat thermogenesis. Cell 157:1279–1291 Rashnonejad A, Ercan G, Gunduz C et al (2018) Comparative analysis of human UCB and adipose tissue derived mesenchymal stem cells for their differentiation potential into brown and white adipocytes. Mol Biol Rep. https://doi.org/10.1007/s11033-018-4156-1 Rosell M, Kaforou M, Frontini A et al (2014) Brown and white adipose tissues: intrinsic differences in gene expression and response to cold exposure in mice. Am J Physiol Endocrinol Metab 306:E945–E964 Ruan CC, Kong LR, Chen XH et al (2018) A2A receptor activation attenuates hypertensive cardiac remodeling via promoting brown adipose tissue-derived FGF21. Cell Metab 28:476–489.e5 Ryu V, Garretson JT, Liu Y et al (2015) Brown adipose tissue has sympathetic-sensory feedback circuits. J Neurosci 35:2181–2190 Ryu V, Watts AG, Xue B, Bartness TJ (2017) Bidirectional crosstalk between the sensory and sympathetic motor systems innervating brown and white adipose tissue in male Siberian hamsters. Am J Physiol Regul Integr Comp Physiol 312:R324–R337 Saito M, Okamatsu-Ogura Y, Matsushita M et al (2009) High incidence of metabolically active brown adipose tissue in healthy adult humans: effects of cold exposure and adiposity. Diabetes 58:1526–1531 Sakamoto T, Nitta T, Maruno K et al (2016) Macrophage infiltration into obese adipose tissues suppresses the induction of UCP1 level in mice. Am J Physiol Metab 310:E676–E687 Sampath SC, Sampath SC, Bredella MA et al (2016) Imaging of brown adipose tissue: state of the art. Radiology 280:4–19 Schlein C, Talukdar S, Heine M et al (2016) FGF21 lowers plasma triglycerides by accelerating lipoprotein catabolism in white and Brown adipose tissues. Cell Metab 23:441–453 Shen H, Jiang L, Lin JD et al (2019) Brown fat activation mitigates alcohol-induced liver steatosis and injury in mice. J Clin Invest 129:2305–2317 Silva FJ, Holt DJ, Vargas V et al (2014) Metabolically active human brown adipose tissue derived stem cells. Stem Cells 32:572–581

53 Soderlund V, Larsson SA, Jacobsson H (2007) Reduction of FDG uptake in brown adipose tissue in clinical patients by a single dose of propranolol. Eur J Nucl Med Mol Imaging 34:1018–1022 Soler-Vázquez MC, Mera P, Zagmutt S et al (2018) New approaches targeting brown adipose tissue transplantation as a therapy in obesity. Biochem Pharmacol 155:346–355 Song CK, Vaughan CH, Keen-Rhinehart E et al (2008) Melanocortin-4 receptor mRNA expressed in sympathetic outflow neurons to brown adipose tissue: neuroanatomical and functional evidence. Am J Physiol Regul Integr Comp Physiol 295:R417–R428 Stanford KI, Middelbeek RJW, Townsend KL et al (2013) Brown adipose tissue regulates glucose homeostasis and insulin sensitivity. J Clin Invest 123:215–223 Stanford KI, Middelbeek RJW, Townsend KL et al (2015) A novel role for subcutaneous adipose tissue in exercise-induced improvements in glucose homeostasis. Diabetes 64:2002–2014 Stanford KI, Lynes MD, Takahashi H et al (2018) 12,13diHOME: an exercise-induced lipokine that increases skeletal muscle fatty acid uptake. Cell Metab 27:1111–1120.e3 Sun K, Kusminski CM, Scherer PE (2011) Adipose tissue remodeling and obesity. J Clin Invest 121:2094–2101 Tan CY, Vidal-Puig A (2008) Adipose tissue expandability: the metabolic problems of obesity may arise from the inability to become more obese. Biochem Soc Trans 36:935–940 Thomou T, Mori MA, Dreyfuss JM et al (2017) Adiposederived circulating miRNAs regulate gene expression in other tissues. Nature 542:450–455 Thoonen R, Ernande L, Cheng J et al (2015) Functional brown adipose tissue limits cardiomyocyte injury and adverse remodeling in catecholamine-induced cardiomyopathy. J Mol Cell Cardiol 84:202–211 Tseng Y-H, Kokkotou E, Schulz TJ et al (2008) New role of bone morphogenetic protein 7 in brown adipogenesis and energy expenditure. Nature 454:1000–1004 van Marken Lichtenbelt WD, Vanhommerig JW, Smulders NM et al (2009) Cold-activated brown adipose tissue in healthy men. N Engl J Med 360:1500–1508 Verdeguer F, Soustek MS, Hatting M et al (2015) Brown adipose YY1 deficiency activates expression of secreted proteins linked to energy expenditure and prevents dietinduced obesity. Mol Cell Biol 36:184–196 Villarroya F, Vidal-Puig A (2013) Beyond the sympathetic tone: the new brown fat activators. Cell Metab 17:638–643 Villarroya F, Cereijo R, Villarroya J, Giralt M (2017a) Brown adipose tissue as a secretory organ. Nat Rev Endocrinol 13:26–35 Villarroya F, Gavaldà-Navarro A, Peyrou M et al (2017b) The lives and times of brown adipokines. Trends Endocrinol Metab 28:855–867 Villarroya F, Cereijo R, Gavaldà-Navarro A et al (2018a) Inflammation of brown/beige adipose tissues in obesity and metabolic disease. J Intern Med 284:492–504

54 Villarroya F, Cereijo R, Villarroya J et al (2018b) Toward an understanding of how immune cells control brown and beige adipobiology. Cell Metab 27:954–961 Villarroya J, Cereijo R, Gavaldà-Navarro A et al (2019a) New insights into the secretory functions of brown adipose tissue. J Endocrinol 243:R19–R27 Villarroya J, Cereijo R, Giralt M, Villarroya F (2019b) Secretory proteome of brown adipocytes in response to cAMP-mediated thermogenic activation. Front Physiol 10:67 Virtanen KA, Lidell ME, Orava J et al (2009) Functional brown adipose tissue in healthy adults. N Engl J Med 360:1518–1525 Wade GN, Gray JM (1978) Cytoplasmic 17β-[3H]estradiol binding in rat adipose tissues. Endocrinology 103:1695–1701 Wang G-X, Zhao X-Y, Meng Z-X et al (2014) The brown fat-enriched secreted factor Nrg4 preserves metabolic homeostasis through attenuation of hepatic lipogenesis. Nat Med 20:1436–1443 Watanabe M, Houten SM, Mataki C et al (2006) Bile acids induce energy expenditure by promoting intracellular thyroid hormone activation. Nature 439:484–489 White JD, Dewal RS, Stanford KI (2019) The beneficial effects of brown adipose tissue transplantation. Mol Aspects Med 68:74–81 Whittle AJ, Carobbio S, Martins L et al (2012) BMP8B increases brown adipose tissue thermogenesis through both central and peripheral actions. Cell 149:871–885

M. Alcalá et al. Wu J, Cohen P, Spiegelman BM (2013) Adaptive thermogenesis in adipocytes: is beige the new brown? Genes Dev 27:234–250 Wu R, Liu XM, Sun JG et al (2017) DJ-1 maintains energy and glucose homeostasis by regulating the function of brown adipose tissue. Cell Discov 3:1–18 Yasuda T, Masaki T, Kakuma T, Yoshimatsu H (2004) Hypothalamic melanocortin system regulates sympathetic nerve activity in brown adipose tissue. Exp Biol Med 229:235–239 Yuan X, Hu T, Zhao H et al (2016) Brown adipose tissue transplantation ameliorates polycystic ovary syndrome. Proc Natl Acad Sci USA 113:2708–2713 Zhang Y, Kerman IA, Laque A et al (2011) Leptinreceptor-expressing neurons in the dorsomedial hypothalamus and median preoptic area regulate sympathetic brown adipose tissue circuits. J Neurosci 31:1873–1884 Zhu Z, Spicer EG, Gavini CK et al (2014) Enhanced sympathetic activity in mice with brown adipose tissue transplantation (transBATation). Physiol Behav 125:21–29 Zhu Q, Glazier BJ, Hinkel BC et al (2019) Neuroendocrine regulation of energy metabolism involving different types of adipose tissues. Int J Mol Sci 20:2707 Zingaretti MC, Crosta F, Vitali A et al (2009) The presence of UCP1 demonstrates that metabolically active adipose tissue in the neck of adult humans truly represents brown adipose tissue. FASEB J 23:3113–3120

5

White and Brown Adipose Tissue in Obesity and Diabetes Brooks P. Leitner and Borja Martinez-Tellez

Contents Distribution and Functions of Human Adipose Tissue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . White Adipose Tissue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Brown Adipose Tissue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Anatomical Sites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Beige Adipose Tissue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

56 56 57 57 58

White Adipose Tissue and Insulin Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Glucose Homeostasis Crosstalk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inflammatory Adiposopathy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ectopic Fat Depots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

58 59 59 59

Activation of Human Brown Adipose Tissue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cold Exposure Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Exercise Activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Food Intake and Thermoregulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

60 60 62 62

Role of Brown Fat in Human Metabolism in Healthy, Obese, and Diabetic Individuals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 BAT Hormone-Like Secretions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Correlations with Obesity and Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Methods for Detecting Human Brown Adipose Tissue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Monitoring of Skin Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Radiolabeled Glucose Analog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tracer and Imaging Alternatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Immunohistochemical or Gene-Expression Confirmation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

64 64 64 65 65

Future Investigations into Human Brown Adipose Tissue Physiology . . . . . . . . . . . . . 66 Dietary Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 B. P. Leitner (*) Department of Internal Medicine and Cellular and Molecular Physiology, Yale University, New Haven, CT, USA e-mail: [email protected] B. Martinez-Tellez Department of Medicine, Division of Endocrinology, and Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, The Netherlands # Springer Nature Switzerland AG 2020 J. Faintuch and S. Faintuch (eds.), Obesity and Diabetes, https://doi.org/10.1007/978-3-030-53370-0_5

55

56

B. P. Leitner and B. Martinez-Tellez Pharmaceutical Compounds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 Gut Microbiota as a New Target to Combat T2D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 Future Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Abstract

It has become increasingly evident that the diversity of adipose tissue types may play distinct and potentially important roles in human physiology. White adipose tissue (WAT), the primary energy storage tissue, is important in homeostasis but when found in excess can predispose individuals to severe insulin resistance and diabetes. Human life is compatible with WAT composing between 4 and 60% of total body mass, pointing to its incredible adaptability. In contrast, brown adipose tissue (BAT), typically thought to occur only in hibernating animals and babies, is becoming recognized for its role in human energy expenditure, hormone production, immune regulation, among others. BAT usually comprises around 0–2% of total body mass; however, recent scientific advances in noninvasive imaging and molecular biology have allowed to explore unknown functions of this dynamic tissue. We discuss here the anatomy and physiology of WAT and BAT in the lean and obese human, and potential mechanisms regarding the interplay within obesity and Type 2 diabetes. Later, we review the current methodology for measuring and detecting WAT and BAT, how to experimentally modulate BAT activity, as well as future investigations to yield greater insight into BAT’s functional role in human health. Keywords

Brown adipose tissue · White adipose tissue · Brown fat · White fat · Insulin resistance

Distribution and Functions of Human Adipose Tissue It is estimated that in 2025, global obesity rates will reach 18% in men and 21% in women (NCD Risk Factor Collaboration 2016), with diabetes prevalence reaching nearly 400 million people globally (Nathan 2015). Obesity, defined clinically by a body mass index (BMI) of greater than 30 kg/m2, is accompanied by an excess of white adipose tissue (WAT). Obesity is the result of long-term energy intake exceeding energy expenditure, being one of the main comorbidities Type 2 Diabetes (T2D). A diagnosis of T2D is most often made with a glycosylated hemoglobin (HbA1C) of
6.5% or a fasting plasma glucose of
126 mg/dl (Association, A. D. 2 2019). T2D is more likely to be obesity-related and can progress to loss of pancreatic beta-cell insulin secretion, often in the background of insulin resistance. Because the risk for T2D is increased substantially by obesity, the mechanisms that we will discuss throughout the chapter will pertain to both obesity and T2D, unless stated otherwise.

White Adipose Tissue Humans have several types of adipose tissue, although the most studied are white adipose tissue (WAT) and brown adipose tissue (BAT). WAT is normally distributed subcutaneously and in the visceral compartments, the latter known as visceral adipose tissue (VAT). The amount of WAT in humans varies a lot between individuals, with minimal levels sustainable with life around 2% of body mass for men and 6% of body mass for

5

White and Brown Adipose Tissue in Obesity and Diabetes

women, and maximal levels reaching over 60% of body mass. In simple terms, the higher the BMI, the higher the WAT accumulation in both compartments. Subcutaneous WAT is found in all areas beneath the skin surface but has a propensity to be stored in central, or proximal, locations. The distribution of subcutaneous WAT differs between men, who typically have an “android” distribution and women, with a “gynoid” distribution (Min and Min 2015). VAT is also found in central locations, however within the abdominal cavity, surrounding vital organs. VAT contributes a much smaller percentage to total body fat (~5% in men and ~3% in women) (Sasai et al. 2015), yet the accumulation of VAT confers greater risk for T2D and cardiovascular disease than subcutaneous WAT. This phenomenon partly explains the occasional metabolically unhealthy, normal weight phenotype, where individuals that do not have BMIs classified as obese suffer from metabolic syndrome comparable to individuals with much higher body mass. Some data show that physical exercise can selectively reduce VAT, even in the absence of significant weight loss. As WAT is a tissue for energy storage, it is evolutionarily designed with the ability to expand to a great extent, so that high energy density lipids can be available even in times of food shortage. In the modern era with food shortage being less of a concern, this expansion has occurred without periods of energy deficit. Though WAT exists in excess in patients with obesity, WAT in itself is not causative of insulin resistance (the inability for insulin to perform its usual functions). Lessons from patients with lipodystrophy demonstrate this fact, as they have nearly nonexistent WAT, but often develop severe T2D. The contributions of excess adiposity to diabetes may be a result of adipose-derived cytokines (adipokines) or accumulation of ectopic lipids in skeletal muscle and the liver that disrupt insulin signaling. Much has been learned since the discovery of WAT as an endocrine organ (the discovery of leptin, as an adipokine) (Zhang et al. 1994), yet there is still much to be investigated.

57

Brown Adipose Tissue The main function of BAT is to generate heat (thermogenesis), principally through dissipation of the proton gradient in the inner mitochondrial membrane by way of uncoupling protein 1 (UCP1) (Cannon and Nedergaard 2004). Thus, as fuel sources including glucose and fatty acids are utilized by the brown adipocyte, rather than the generation of adenosine triphosphate (ATP), heat is released, resulting in energy-depleting thermogenesis. BAT is extremely important in maintaining euthermia in the hibernating animal during prolonged periods of fasting in cold temperatures. Though the depots of human BAT were extensively defined nearly 50 years ago by autopsy (Heaton 1972), advances in noninvasive imaging have brought a resurgence in the interest in BAT. Classically thought only to exist in the interscapular adipose tissue region of human newborns, 18F-Fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) combined with X-ray computed tomography (CT) studies have shown that active BAT exists in a large portion of the adult population, and can be reliably activated by cold (Cypess et al. 2009; van Marken Lichtenbelt et al. 2009) and by other means. Indeed, over 450 publications on PubMed have studied adult BAT in humans since just 2008. BAT’s functions include substrate metabolism, immune system modulation, endocrine functions, and others. To begin a thorough understanding of BAT function in adults, we have characterized the depots of adult men and women with and without obesity (Leitner et al. 2017; Martinez-Tellez et al. 2019a).

Anatomical Sites Generally, BAT lines visceral locations surrounding major vasculature in the abdomen, neck, and axilla, vital organs including the kidneys and adrenal glands, and alongside the sympathetic trunk. The highest proportion of BAT exists in the supraclavicular region, making

58

it the most commonly studied BAT depot across various studies, followed by the paraspinal, cervical, abdominal (mostly retroperitoneal), axillary, and mediastinal (Leitner et al. 2017). Previous evidence showed that newborns have huge amounts of subcutaneous BAT in the dorsocervical area, as adequate skeletal muscle has not yet been developed for shivering or activity thermogenesis. It has been thought that this subcutaneous BAT disappeared when the newborn grew older; however, recent evidence suggests that it could be still present in young healthy adults, mostly in women (Martinez-Tellez et al. 2019a; Kim et al. 2019). The discovery of this new depot will boost research.

Beige Adipose Tissue Beige and/or brite adipose tissue has been discovered as an inducible form of brown adipose tissue, with morphological features between those of white adipocytes and brown adipocytes, however physiological functions (thermogenesis) of BAT (Wu et al. 2012; Jespersen et al. 2013) remain under intense investigation. In humans, very few studies have been able to characterize anatomical differences throughout the human body, with both functional and biochemical confirmation (Cypess et al. 2013). We have also shown that depots outside of these listed likely have very little capacity for browning or the conversion of white to brown adipocytes; however, depots currently harnessing metabolically active adipocytes comprise up to 5% of total body fat, thus making BAT an organ of appreciable size in adult humans. Though anatomical characterization has come to higher resolution in recent years, it is unclear whether or not there are differential functions harbored by white adipocytes or brown adipocytes that exist in different regions. As most functions seem to operate at an organismwide level, impactful studies can still be conducted without this knowledge. Yet, as noninvasive imaging and other biochemical techniques become more advanced, perhaps soon we will be able to create a functional atlas of human WAT

B. P. Leitner and B. Martinez-Tellez

and BAT. It is interesting that most anatomy textbooks do not have a chapter that maps adipose tissue. Maybe that points to our need to better understand adipocytes in all forms (Zwick et al. 2018).

White Adipose Tissue and Insulin Resistance WAT can account for as little as 4% of total body mass in patients with congenital generalized lipodystrophy (Lima et al. 2016), a disease characterized by the absence of WAT, and as much as nearly 60% of body mass in patients with morbid obesity (Shah and Braverman 2012). Adipose tissue expansion by hypertrophy (increase in adipocyte size) or hyperplasia (increase in adipocyte number) is frequently followed by unfavorable metabolic consequences, such as insulin resistance and inflammation, and as such, WAT plays a major role in the development of insulin resistance. Insulin, a major anabolic hormone, mediates an integrated metabolic response in the presence of nutrients, and insulin signaling is highly active in the adipocytes of lean and obese humans. Most importantly, insulin’s role in the white adipocyte is to suppress lipolysis and stimulate glucose uptake. In the lean individual, these functions are tightly regulated to ensure no excessive freeing of fatty acids and the disposal of glucose. However, leading up to the development of and in the setting of T2D, insulin resistance ensues, manifesting as both blunted insulin signaling in adipocytes, and reduced insulin receptor content (Petersen and Shulman 2018). Functionally, insulin’s main roles in the adipocyte, to stimulate glucose uptake and to suppress lipolysis are less effective. The effects of insulin resistance lead to an excess of plasma insulin, non-esterified fatty acids, and glucose levels, and implicates WAT as a major player in the pathogenesis of insulin resistance. Interestingly, WAT plays a small role in whole-body glucose disposal (less than 5%), however has a significant impact on the development of insulin resistance. Several mechanisms

5

White and Brown Adipose Tissue in Obesity and Diabetes

have been proposed for WAT’s role in the pathogenesis of T2D, despite a seemingly minor participation in glucose disposal. Most convincingly, WAT dysfunction includes altered crosstalk with skeletal muscle and liver at maintaining energetic homeostasis and chronic low-grade inflammation.

Glucose Homeostasis Crosstalk There is substantial coordination between the skeletal muscle, liver, and WAT to maintain normoglycemia in the fed and the fasted states. As humans transition to the fasted state (hours after the previous feeding), leptin and the hypothalamic–pituitary–adrenal (HPA) axis become activated to regulate WAT lipolysis, in order to free fatty acids to the plasma and to the liver for gluconeogenesis (Perry et al. 2018). This integrated response causes a whole-body shift from carbohydrate to fat oxidation. Studies have shown that this coordinated response may be altered in obese men, suggesting that nonesterified fatty acids are not released as readily, resulting in a net storage of fat. In addition, insulin’s roles in suppressing WAT lipolysis and endogenous glucose production (from the liver) become less effective, which has been suggested as a link between WAT inflammation and the development of hyperglycemia (Roden and Shulman 2019).

59

treatability of obesity-induced inflammation came from a clinical trial in obese humans, where Amlexanox, an anti-inflammatory drug typically used in the treatment of asthma, improved glycemic control in a subset of obese, T2D (Oral et al. 2017). Clearly, excess WAT and obesity are accompanied by multiple mechanisms that factor into the development of insulin resistance and diabetes, yet it is important to mention that obesity is not required for the development of these conditions.

Ectopic Fat Depots

Inflammatory Adiposopathy

WAT is not the only player in the development of T2D. Patients with lipodystrophy lacking adipocytes, and thus all adipose-derived hormones including leptin, often become hyperphagic due to the absence of leptin’s hungersuppressing effect. With the incapacity to store excess food intake in adipocytes, ectopic lipids are stored in skeletal muscle and the liver, sometimes to extreme extents. In the setting of massively increased ectopic lipid storage, patients without treatment often develop severe insulin resistance and poorly controlled diabetes, which highlights the role of ectopic lipids rather than excess WAT in the causal pathway of insulin resistance (Grundy 2015). It is possible that this same mechanism could underlie non-lipodystrophic patients who develop T2D, with contributions from genetics, epigenetics, and other factors.

Inflammation in WAT has been characterized by inadequate tissue vascularization, fibrosis, and hypoxia, which develop in the setting of increased WAT mass and cell size. Thus, obesity and the accompanying excess of WAT has been characterized as a state of chronic low-grade inflammation, with possible impaired immune function and activation of stress pathways. Much research has been dedicated to elucidate the mechanisms of WAT inflammation, including upregulation of the inflammatory cytokines tumor necrosis factor (TNF alpha), interleukin (IL)-1B, and IL-6 within adipose depots. Evidence for

Brown Adipose Tissue and Insulin Resistance Preclinical models have suggested that BAT is a great tool to combat adiposity and T2D. Some of these studies have demonstrated that the transplantation of interscapular BAT from lean to obese mice, induced a significant weight loss and improved levels of HbA1C, alleviating insulin resistance. This is the main reason why this tissue has aroused a great interest in human physiology. Although human clinical studies have developed interventions, based on cold exposure, to activate and recruit the amount of BAT in obese and T2D individuals, they have failed to

60

replicate the positive effects of preclinical models (Jensen 2015). The main reason could be that human BAT can represent as little as 1% of total body mass, whereas in preclinical models BAT reaches up to 30–40% of the total body mass. Moreover, it is important to note that BAT consumes glucose and fatty acids, and brown adipocytes have glucose transporter 1 (GLUT1, non-insulin-dependent) and 4 (GLUT4, insulindependent). The most used technique to quantify BAT in humans is 18F-FDG-PET/CT scan, which is based on a glucose tracer. This technique is also used to quantify BAT in T2D. As one can imagine, in the scenario of insulin resistance this technique is far less accurate for the quantification of such tissue, which hampers understanding of the role of BAT in insulin resistance in humans.

Activation of Human Brown Adipose Tissue The interest in BAT lies in its previously mentioned ability to uncouple ATP production from the electron transport chain, providing a means to “waste” energy in the form of heat. Studies that have attempted to examine the maximal energy expending capacity for BAT have been difficult to perform in humans, but have ranged from 5 to 730 kcal/day at maximal activation (Ruiz et al. 2018; Marlatt et al. 2018). These measures range from clinically meaningless, to having a measurable effect on reducing weight. Because BAT is inactive in thermoneutral resting conditions, maximal thermogenesis must be measured in the active state. Researchers have attempted many approaches to BAT activation, including cold exposure, exercise, and dietary/ pharmacological modulation (Ruiz et al. 2018) (see Fig. 5.1). Most often, cold exposure is used to study active BAT. This is a reasonable method to use, as it highlights BAT’s most obvious role in nature: non-shivering thermogenesis to defend against the cold. Cold is sensed by free nerve endings in the skin, and the hypothalamus begins a coordinated whole-body response to defend

B. P. Leitner and B. Martinez-Tellez

core body temperature: intense vasoconstriction occurs at the distal extremities to shunt warm blood to vital organs, contributing to a slowed heart rate. Even at temperatures too low to activate detectable shivering, metabolic rate increases (up to 17% above resting in lean men and 6% above resting in obese men) (Brychta et al. 2019). The blunted response in non-shivering thermogenesis in obese men is likely due to a thicker “shell,” and perhaps greater insulation from cold exposure. This insulation requires less heat production in response to the same cold stimulus, as the heat is trapped in the core, and loss is prevented. If this is the sole mechanism for reduced BAT activity in obese men, it may be expected that pharmacological agents may yield more success for energy expenditure than what cold exposure can reveal.

Cold Exposure Techniques Methods for studying cold-induced thermogenesis and BAT in humans include ambient cold air exposure, the wearing of liquid-perfused cooling suits, and placing the feet on ice blocks. It is uncertain whether all of these methods are comparable, yet studies suggest that the degree of BAT activation is likely reproducible when maintaining a standardized protocol (Fraum et al. 2019). All methodologies considered, BAT is quickly activated in response to cold exposure (Leitner et al. 2018), it can contribute to coldinduced energy expenditure in the absence of shivering, and BAT metabolizes a combination of both fatty acids and glucose when active. In addition, cold-acclimation studies have demonstrated that BAT volume and metabolic activity can be increased over the course of a week in both lean and obese individuals (Lee et al. 2014; Hanssen et al. 2016). Detectable BAT is found in most obese patients, though consistently to a lesser extent than their lean counterparts. One of the only studies that has rigorously measured BAT in type 2 diabetic

5

White and Brown Adipose Tissue in Obesity and Diabetes

Fig. 5.1 This schematic figure summarizes the main issues discussed in the present chapter. 18F-FDG

61

18F-fluorodeoxyglucose, BAT brown adipose tissue, CT computed tomography, DEXA Dual-energy X-ray

62

patients has shown that an improvement in insulin sensitivity following chronic cold exposure, can be mostly attributed to skeletal muscle adaptation rather than BAT glucose uptake (Hanssen et al. 2015), thus the utility of chronic BAT activation for energy expenditure must certainly be considered carefully. Importantly, nearly all studies that have examined subcutaneous WAT for features of BAT in response to chronic cold exposure, have yielded negative results. Recently, a new study nicely shows that human BAT is rapidly activated upon cold exposure, achieving its maximum activity after 35 min of cold exposure (Oreskovich et al. 2019). This study was performed by a dynamic magnetic resonance imaging (MRI) scan. After 2 h of cold exposure, a warm-up phase during 30 min followed, and no replenishment of the lipid content of the BAT depots ensued. This study revealed that BAT is only active during the first part of the cooling protocols, questioning much evidence published so far. To date the most used cooling protocols to activate BAT applied a total duration of 2 h; therefore, they have quantified BAT when it was not truly activated.

B. P. Leitner and B. Martinez-Tellez

browning effect is caused by the exercise, by the temperature, or by the combination of both stimuli (McKie et al. 2019). Regarding humans, the evidence is even more contradictory. There are only a few cross-sectional studies that showed that trained-individuals had lower levels of BAT 18F-FDG uptake in comparison to sedentary controls. Moreover, we recently demonstrated that objectively measured physical activity by accelerometers and cardiorespiratory fitness protocols, were not associated with BAT 18 F-FDG uptake (Acosta et al. 2019). Surprisingly, we observed that handgrip strength was positively and slightly related with BAT 18F-FDG uptake, suggesting that maybe resistance training could have a different role in terms of BAT activation in comparison to endurance training. However, much more studies are needed (Martinez-Tellez et al. 2019b). Lastly, only a few studies performed exercise interventions including BAT 18F-FDG uptake and browning markers in humans, and again the results are quite controversial.

Food Intake and Thermoregulation

Exercise is a non-pharmacological tool that induces a myriad of physiological adaptations, enhancing human cardiovascular health and insulin sensitivity in almost every single human being. Therefore, it is biologically plausible that exercise will affect BAT function, although it is unknown in which direction. Preclinical studies have suggested that exercise could increase BAT function and induce browning in almost all WAT depots (Stanford et al. 2015). However, it seems that most of these studies were not performed under strictly thermoneutral conditions, rendering it impossible to discriminate whether this

Recently, we demonstrated that BAT activity is not related to energy intake assessed by an ad libitum meal and by 24-h dietary recalls (Sanchez-Delgado et al. 2020). Moreover, we did not detect the role of BAT in the regulation of appetite-related sensations either before or after the subjects ate. In a submitted study, we also observed that BAT activity was not related to the adherence to a Mediterranean diet, which is one of the healthiest diets. On the other hand, an independent study showed that the oxygen consumption of BAT depots increased after a single meal intake. It seems that BAT is not playing a role in appetite perception, energy, or nutrition intakes, although it could be playing a minimal role during meal intake.

Fig. 5.1 (continued) absorptiometry, FFA free fatty acids, H20 water, MRI magnetic resonance imaging, PET

positron emission tomography. This image is courtesy by The Voice Of Science

Exercise Activation

5

White and Brown Adipose Tissue in Obesity and Diabetes

Role of Brown Fat in Human Metabolism in Healthy, Obese, and Diabetic Individuals One option to prevent and combat obesity and related comorbidities is to increase thermogenesis, which leads to increased energy expenditure. In mice, BAT is responsible for 20% (Blondin et al. 2017) of both resting metabolic rate and adaptive thermogenesis, i.e., cold-induced thermogenesis (CIT) and meal-induced thermogenesis (MIT) (Nathan 2015), and can account for up to 60% of total energy expenditure when fully stimulated. Human BAT becomes metabolically active upon cold exposure in most individuals. However, a recent study nicely demonstrated that the contribution to the increase observed in CIT is almost negligible (Din et al. 2016; Carpentier et al. 2018). The same research group, demonstrated that BAT was active after eating a carbohydrate-rich meal to a similar extent than during mild cold exposure, yet its contribution to the increase in MIT is quite low. These novel studies confirm that BAT is contributing to human thermogenesis, but in a lower proportion than was thought at the beginning. What is the main role of BAT in the human metabolism? After 10 years of thoughtful research in human trials and mice studies we still do not know, although several new roles have been attributed, such as a secretory organ orchestrating the shivering and non-shivering responses or immune system modulation, among others.

BAT Hormone-Like Secretions Some specialists suggest that the role of BAT in the human metabolism is negligible because it represents only 1% of total body mass. On the other hand, humans have similarly small organs (i.e., thyroid, adrenal, pituitary) that have very important roles in metabolism, so it could be reasonably expected that BAT has unknown and relevant functions. BAT has the ability to secrete several hormones (batokines) that could coordinate/orchestrate the responses of other tissues to

63

different stimuli. For instance, we know that when humans are exposed to cold there is an increase of the energy expenditure, which could be explained by the contribution of two thermogenic tissues (BAT and skeletal muscles) (Villarroya et al. 2017). One of the hypotheses that is open for discussion is that BAT could be releasing a set of batokines that could boost the involvement of skeletal muscle during cold exposure. BAT has been proposed to interact with bone (via IGFBP2), WAT, brain, pancreas, heart (via FGF-21 or IL6), and liver (IGF1), and therefore, impact tissue plasticity and metabolism. A research group from Copenhagen performed the first human BAT secretome. In this particular study, they discovered that ependymin-related protein 1 (EPDR1) was a novel batokine important for brown fat commitment (Deshmukh et al. 2019). They suggest that this batokine could be involved in the regulation of human metabolism.

Correlations with Obesity and Diabetes Originally, it has been thought that obesity is negatively related to the amount of BAT; however, we recently discovered that obesity was positively related to BAT volume in 150 young healthy adults. This controversial finding could be explained by several factors: (1) BAT normally is measured with a glucose analog. Since the individuals of our study were quite young (12,000 individuals (Sandholm et al., 2012). Additionally, although not genome-wide significant, a strong association with diabetic nephropathy (defined as persistent macroalbuminuria or ESRD) was also seen (intronic SNP rs7588550 in the ERBB4 gene). In addition to increasing sample sizes, to overcome limitations of these early GWASs due to imprecise and variable phenotypic heterogeneity, Sandholm et al. analyzed a range of ACR- and eGFR-based subphenotypes, which span different stages and severities of DKD in a meta-analysis of 4 large cohorts (Sandholm et al., 2017). However, despite being well-powered to detect variants with a MAF  10% and an OR  1.55, no SNPs reached genome-wide significance in this study. Suggestive associations for ESRDbased phenotypes (“ESRD vs. no DKD” and “CKD + DKD vs. eGFR >60, normoalbuminuric”) were detected in CNTNAP2 (rs1989248), PTPN13 (rs61277444), and AFF3 (rs7562121). As many of the samples included in this study overlap with those in the previous GWAS from the GENIE consortium, this suggestive association at AFF3 does not provide independent replication of the previously reported association. Interestingly, independent replication was observed in this study for signals reported at ELMO1 (Shimazaki et al., 2005), the MYO16IRS2 locus on chromosome 13q (Pezzolesi et al., 2009b), and SIK1 (Sambo et al., 2014).

Combined Databases Following a study design similar to that of Sandholm et al. (Sandholm et al., 2017), the SUrrogate markers for Micro- and Macrovascular hard endpoints for Innovative diabetes Tools (SUMMIT) consortium performed the largest T2D DKD GWAS composed of > 20,000 T2D

230

patients using eight dichotomous and quantitative DKD subphenotypes (van Zuydam et al., 2018). To further increase sample size, a combined T1D and T2D meta-analysis that included samples of European and Asian ancestry was performed. In total, the sample size of this analysis exceeded 40,000 subjects. Despite this, the yield for discovery of novel loci was modest. One SNP, rs2206136 in PLCB4, reached significance with the “CKD” phenotype (P-value ¼ 2.1
108) in discovery GWAS but not in replication analyses. A novel signal at rs9942471, a position 7 kb upstream of GABRR1, was associated with increased microalbuminuria risk in European subjects. Additionally, the combined metaanalysis for eGFR identified a new genomewide association mapping near SSB. Interestingly, as the authors note, while this study aimed to overcome some of the limitations of earlier studies, its significantly larger sample size came with increased phenotypic and, likely genetic, heterogeneity that may have impacted its ability to detect additional genetic associations.

Coding vs Noncoding Variants SNPs included in these studies mostly map to nonprotein coding regions, which limits the interpretation of the candidate SNP’s role in disease susceptibility. Similarly, identified SNPs may be in linkage disequilibrium with causal variants some distance from the identified association, e.g., a causal variant may localize to a gene several hundred kilo-basepair away from the detected association, thereby complicating investigations into the functionality of an associated SNP. Importantly, completion of the National Heart, Lungs, and Blood Institute’s Exome Sequencing Project led to the development of a new generation of commercially available genotyping arrays that, in addition to common noncoding variation, now includes coding or ‘exome’ variants with MAFs as low as 0.5% across the genome (Auer et al., 2016). Using this technology, the Juvenile Diabetes Research Foundation funded Diabetic Nephropathy Collaborative Research Initiative (JDRF-

C. A. Simeone et al.

DNCRI) recently performed the largest T1D DKD GWAS, with 19,406 T1D individuals with and without kidney disease, and identified 16 novel genome-wide significant associations with various dichotomous phenotypes (Salem et al., 2019). The strongest association (rs55703767, a common missense variant in COL4A3) was a protective variant against DN, linked to lower glomerular basement membrane thickness. In contrast to the SUMMIT study, which included T1D and T2D individuals of European and Asian ancestry from 16 different studies genotyped on various platforms, the JDRF-DNCRI study benefited from uniform genotyping, quality control procedures, and standardized phenotype definitions. Adoption of this study design, coupled with an increased sample size, helped foster the discovery of several novel associations with DKD in this study.

Ethnic Patterns Although the majority of genetic studies of DKD have focused on subjects of European ancestry, several studies have included individuals of different ethnicities and demonstrated potential population-specific signals. The majority of these efforts have, however, been in patients with T2D. In the only trans-ethnic meta-analysis of T2D DKD patients, conducted as part of the Family Investigation of Nephropathy and Diabetes (FIND) study, Iyengar et al. identified SNP rs955333, located between SCAF8 and CNKSR3, among patients of American Indian, Europeans, and Mexican ancestries (Iyengar et al., 2015). No SNP reached genome-wide significance in African American T2D patients, although suggestive associations were seen in APOL1 and MYH9 genes. As APOL1 is a well-known ESRD susceptibility locus in African Americans, this signal may be due to nonDKD influences. In addition to early GWASs that first reported associations at ELMO1, a more recent GWAS in T2D DKD Japanese patients identified a genomewide significant association with rs56094641 in FTO as a susceptibility marker for DKD (Taira et al., 2018). The FTO locus has repeatedly been

17

The Genetic Basis of Diabetic Kidney Disease

reported to be associated with obesity; however, its association with DKD was not affected by adjustment for BMI in this study. Interestingly, this association was not replicated in European T2D DKD patients. Many studies of T2D attributed ESRD in African Americans have reported additional significant loci, including SLITRK3, ENPP7, GNG7, SFI1, and LIMK2 (Guan et al., 2019, Palmer et al., 2014). With regard to T1D DKD, there have not been any studies to date to address the genetics of T1D DKD in African Americans; intense effort is needed to expand this area of research.

Contributions of Low Frequency and Rare Variations in DKD Patients Similar to other common, complex diseases, most of the variants identified through GWASs of DKD only explain a small proportion of its overall risk. It has been proposed that some of this ‘missing heritability,’ which is not accounted for by common variation, may be attributed to additional risk conferred by low frequency (0.5%  MAF < 5%) and rare (MAF < 0.5%) variation (Lee et al., 2014; Manolio et al. 2009). Although next-generation GWASs are beginning to explore their role in DKD susceptibility, challenges for investigating low frequency and rare variation persist in all complex disease genetics. Among these, the sample size requirement needed to detect a robust association with low frequency and rare variation remains a major hurdle.

Statistical Challenges For single variant association tests, the sample sizes to achieve 80% power (at a significance level of 5
108 with an OR ¼ 1.4) would need to be 6400, 54,000, and 540,000 for variants with MAFs ¼ 0.1, 0.01, and 0.001, respectively (Lee et al., 2014). Unfortunately, current DKD cohorts do not exceed 50,000 patients. Additionally, while newer commercial genotyping arrays do include as many as 200,000–250,000 low frequency and rare variants, these arrays are limited

231

to the variants included in the array’s design, such that novel variants and those not selected for inclusion cannot be assessed. Finally, while NGS-based approaches (e.g., WES and WGS) are ideal for discovering and interrogating low frequency and rare variation, these approaches still remain costly at scale, despite their continuous declining cost and, thereby, have had limited utility in the field. Despite these challenges, WES and GWASs including low frequency and rare variants have been utilized with some success to explore the contribution of these classes of variants in DKD. In 2017, Sandholm et al. performed WES in 997 T1D DKD subjects (Sandholm et al., 2017). While no variants reached exome-wide significance (P-value < 2.5
107) for single variant and gene aggregation tests, nominal (P-value < 9
105) associations with rare missense alleles were identified; the strongest association was observed at an intronic SNP within NVL (rs188427269, MAF ¼ 0.2%, and P-value ¼ 3.3
107). Importantly, the lack of exomewide significance in this study is likely due to its modest sample size, as 997 patients may not be enough to detect significant associations with rare variants. In the T1D DKD GWAS from the JDRF-DNCRI, Salem et al. reported several associations with low frequency variants included on a commercial genotyping array associated with ESRD, microalbuminuria, and DN (Salem et al., 2019). The lowest P-value was observed at low frequency intronic variants in PAPLN (rs113554206, MAF ¼ 1.2%, and P-value ¼ 5.39
107). Given the excess rate of ESRD in African Americans relative to European Americans, Guan et al. evaluated the impact of low-frequency variants in 47 candidate genes involved in kidney structure (e.g., podocyte, glomerular basement membrane, and renal tubular cell genes) with ESRD in approximately 5000 African American subjects (Guan et al., 2016). After excluding carriers of APOL1 risk alleles, statistically significant associations were observed at two missense variants, located in CLDN8 and COL4A3. A subsequent exomewide association study by the same group

232

identified suggestive associations at OTUD7B, IFITN3, and DLGAP5 (Guan et al., 2018). While these studies are the first to begin investigating the role of low frequency and rare variants in DKD, these associations should be interpreted with caution due to an overall lack of genome-wide significance due to their limited sample sizes. These studies may suggest that low frequency or rare variants do not contribute significantly to the underlying genetic component of DKD, as would be seen in monogenic conditions, but may still modestly impact its susceptibility.

From Genetic Causes of DKD to Personalized Therapies Although progress in personalized therapeutics in DKD has been limited, genetic studies in DKD have shown promise toward translating robust findings to improved patient care. Pharmacogenomics examines how genetic variation can impact beneficial or adverse reactions to therapies and, using genetic data to predict therapeutic response, is beginning to emerge in clinical practice (Roden et al., 2019). This approach has been applied to evaluate reactions to therapies for DKD patients. One of the earliest studied pharmacogenomic loci in DKD is the insertion-deletion polymorphism of the ACE gene (rs4646994), where the insertion (I) or deletion (D) of a 287 basepair Alu repeat in intron 16 of ACE affects patient responses to angiotensin converting enzyme (ACE) inhibitors, a first-line treatment for DKD. In T1D DKD patients, early reports indicated that individual homozygous for the deletion allele (DD) was more likely to progress to ESRD and lacked a response to renoprotective therapies. However, a study from the Steno Diabetes Center demonstrated that there is no difference in the renoprotective effects in either II or DD individuals (Andersen et al., 2003).

C. A. Simeone et al.

Angiotensin Modulators These conflicting results in T1D DKD patients could result from the modest sample sizes of these studies or the efficacies of the drugs examined. More recently, Wang et al. investigated the renoprotective efficacy of valsartan, an angiotensin receptor blocker (ARB), in T2D patients carrying the ACE I/D polymorphism and reported an increased risk of developing DKD among carriers of the D allele (Wang et al., 2016). They also observed a beneficial decrease in albuminuria levels for patients with the ID and DD genotypes when treated with valsartan. This observation is likely due to decreased plasma ACE activity in patients carrying this polymorphism. While no genetic studies of DKD have reported a significant association with CYP2C9, two coding polymorphisms, *2 (Arg144Cys, rs1799853) and *3 (Ile359Leu, rs1057910), can influence CYP2C9 metabolism of ARBs. As ARBs can improve renal function in DKD patients, some studies have examined pharmacological responses with these variants. Lajer et al. described that patients without the CYP2C9*3 polymorphism had a significant change in systolic blood pressure after 4 months compared to *3 carriers. However, both *3 and non*3 carriers had no significant difference in urinary albumin excretion during the study period (Lajer et al., 2007).

Future Directions Overcoming DKD’s phenotypic heterogeneity has proven to be among the most challenging. As a progressive disease, the lack of consistent findings across studies can, in part, be attributed to the array of clinical definitions established by different studies. Since most genetic approaches are inherently cross-sectional, investigators typically examine multiple phenotypes that span all stages and presentations of renal disease. This

17

The Genetic Basis of Diabetic Kidney Disease

approach has drawbacks, as a patient’s renal status could change over time (i.e., a microalbuminuric patient reverts to normoalbuminuria or, alternatively, progresses to proteinuria or ESRD), leading to misclassification. Misclassification bias then could result in a significant number of false-negative associations. Indeed, longitudinal investigations of DKD have shed new light on the natural history of this disease and its heterogeneous nature ( Perkins et al., 2010, Skupien et al., 2012, Krolewski and Bonventre, 2012, Krolewski, 2015). Additionally, the rate of renal function decline varies widely among DKD patients; perhaps, genetic factors influence whether this decline is slow, where ESRD is reached after decades of diabetes, or decline is rapid and progression to ESRD occurs in as little as a few years after the onset of diabetes (Skupien et al., 2012, Krolewski and Bonventre, 2012, Krolewski, 2015). Because of the heterogeneity of the subphenotypes of DKD, considering such disparate patients simultaneously likely poses challenges to uncovering the genetic basis of DKD. Additionally, it is possible that a subset of DKD patients have nondiabetic kidney disease (NDKD) coincident with diabetes or concurrent DKD and NDKD. Renal biopsies from patients with diabetes and kidney disease suggest that as many as 30–80% of patients diagnosed with DKD actually had kidney disease attributed to nondiabetic causes (Haider et al., 2011, Sharma et al., 2013, Zhuo et al., 2013). Importantly, this has major implications in terms of patient care, monitoring, and family planning, as well as for research studies aimed at understanding the factors that contribute to DKD. To begin investigating this, we have recently shown that a subset of ‘DKD’ patients carry rare pathogenic variants indicative of NDKD, e.g., variants in COL4A3 (associated with focal segmental glomerulosclerosis, thin basement membrane nephropathy, and Alport Syndrome) and REN (associated with autosomal dominant tubulointerstitial kidney disease) (Lazaro-Guevara et al., 2020).

233

Large research consortiums are now bringing together investigators across the globe to combine resources and enhance the cohort sizes of current genetic studies, such as the Juvenile diabetes research foundation-Diabetic nephropathy collaborative research initiative (JDRF-DNCRI) most recent T1D DKD GWAS. Even though establishing large cohorts increases statistical power, how many samples are sufficient to accurately identify all of the contributing genetic variation underlying DKD? Is there a sample size threshold that diminishes any further efforts of larger GWASs?

Epigenomics In addition to variation at the DNA sequence level, increasing research shows that epigenetic and epigenomic mechanisms, i.e., heritable changes in gene expression, including DNA methylation and histone modifications, which do not alter the sequence of DNA, are involved in DKD pathogenesis (Kato and Natarajan, 2019). Nucleic acid and chromatin histone complex modifications elicit changes in gene expression by affecting the binding of potential transcriptional regulators. It has been demonstrated that “metabolic memory” of previous metabolic dysregulation exists, where patients with longstanding diabetes can still experience complications even after intense glucose control, highlighting prolonged modification of gene expression patterns in DKD risk (Reidy et al., 2014). Therefore, identifying epigenetic signatures could lead to new treatments and diagnostic biomarkers for DKD initiation and progression.

References Alicic RZ, Rooney MT, Tuttle KR (2017) Diabetic kidney disease: challenges, progress, and possibilities. Clin J Am Soc Nephrol 12:2032–2045 Altshuler D, Brooks LD, Chakravarti A, Collins FS, Daly MJ, Donnelly P (2005) A haplotype map of the human genome. Nature 437:1299–1320

234 Anders HJ, Huber TB, Isermann B, Schiffer M (2018) CKD in diabetes: diabetic kidney disease versus nondiabetic kidney disease. Nat Rev Nephrol 14:361–377 Andersen S, Tarnow L, Cambien F, Rossing P, Juhl TR, Deinum J, Parving HH (2003) Long-term renoprotective effects of losartan in diabetic nephropathy: interaction with ACE insertion/deletion genotype? Diabetes Care 26:1501–1506 Auer PL, Reiner AP, Wang G, Kang HM, Abecasis GR et al (2016) Guidelines for large-scale sequence-based complex trait association studies: lessons learned from the NHLBI exome sequencing project. Am J Hum Genet 99:791–801 Borch-Johnsen K, Norgaard K, Hommel E, Mathiesen ER, Jensen JS, Deckert T, Parving HH (1992) Is diabetic nephropathy an inherited complication? Kidney Int 41:719–722 Brenner BM, Cooper ME, De Zeeuw D, Keane WF, Mitch WE et al (2001) Effects of losartan on renal and cardiovascular outcomes in patients with type 2 diabetes and nephropathy. N Engl J Med 345:861–869 Caramori ML, Fioretto P, Mauer M (2003) Low glomerular filtration rate in normoalbuminuric type 1 diabetic patients: an indicator of more advanced glomerular lesions. Diabetes 52:1036–1040 Faronato PP, Maioli M, Tonolo G, Brocco E, Noventa F et al (1997) Clustering of albumin excretion rate abnormalities in Caucasian patients with NIDDM. The Italian NIDDM Nephropathy Study Group. Diabetologia 40:816–823 Fioretto P, Steffes MW, Barbosa J, Rich SS, Miller ME, Mauer M (1999) Is diabetic nephropathy inherited? Studies of glomerular structure in type 1 diabetic sibling pairs. Diabetes 48:865–869 Fioretto P, Caramori ML, Mauer M (2008) The kidney in diabetes: dynamic pathways of injury and repair. The Camillo Golgi Lecture 2007. Diabetologia 51:1347 Freedman BI, Bostrom M, Daeihagh P, Bowden DW (2007) Genetic factors in diabetic nephropathy. Clin J Am Soc Nephrol 2:1306–1316 Gaede P, Tarnow L, Vedel P, Parving HH, Pedersen O (2004) Remission to normoalbuminuria during multifactorial treatment preserves kidney function in patients with type 2 diabetes and microalbuminuria. Nephrol Dial Transplant 19:2784–2788 Germain M, Pezzolesi MG, Sandholm N, Mcknight AJ, Susztak K et al (2015) SORBS1 gene, a new candidate for diabetic nephropathy: results from a multi-stage genome-wide association study in patients with type 1 diabetes. Diabetologia 58:543–548 Gu HF (2019) Genetic and epigenetic studies in diabetic kidney disease. Front Genet 10:507 Guan M, Ma J, Keaton JM, Dimitrov L, Mudgal P et al (2016) Association of kidney structure-related gene variants with type 2 diabetes-attributed end-stage kidney disease in African Americans. Hum Genet 135:1251–1262 Guan M, Keaton JM, Dimitrov L, Hicks PJ, Xu J et al (2018) An exome-wide association study for type

C. A. Simeone et al. 2 diabetes-attributed end-stage kidney disease in African Americans. Kidney Int Rep 3:867–878 Guan M, Keaton JM, Dimitrov L, Hicks PJ, Xu J et al (2019) Genome-wide association study identifies novel loci for type 2 diabetes-attributed end-stage kidney disease in African Americans. Hum Genomics 13:21 Haider DG, Peric S, Friedl A, Fuhrmann V, Wolzt M, Horl WH, Soleiman A (2011) Kidney biopsy in patients with diabetes mellitus. Clin Nephrol 76:180–185 Hathaway CK, Chang AS, Grant R, Kim HS, Madden VJ, Bagnell CR Jr, Jennette JC, Smithies O, Kakoki M (2016) High Elmo1 expression aggravates and low Elmo1 expression prevents diabetic nephropathy. Proc Natl Acad Sci U S A 113:2218–2222 Iyengar SK, Sedor JR, Freedman BI, Kao WH, Kretzler M et al (2015) Genome-wide association and trans-ethnic meta-analysis for advanced diabetic kidney disease: family investigation of nephropathy and diabetes (FIND). PLoS Genet 11:e1005352 Kato M, Natarajan R (2019) Epigenetics and epigenomics in diabetic kidney disease and metabolic memory. Nat Rev Nephrol 15:327–345 Krolewski AS (2015) Progressive renal decline: the new paradigm of diabetic nephropathy in type 1 diabetes. Diabetes Care 38:954–962 Krolewski AS, Bonventre JV (2012) High risk of ESRD in type 1 diabetes: new strategies are needed to retard progressive renal function decline. Semin Nephrol 32:407–414 Lajer M, Tarnow L, Andersen S, Parving HH (2007) CYP2C9 variant modifies blood pressure-lowering response to losartan in Type 1 diabetic patients with nephropathy. Diabet Med 24:323–325 Lander ES, Linton LM, Birren B, Nusbaum C, Zody MC et al (2001) Initial sequencing and analysis of the human genome. Nature 409:860–921 Lazaro-Guevara, J., Morales, J. F., Wright, A. H., Gunville, R., Frodsham, S. G., et al. 2020. Targeted next-generation identifies pathogenic variants in kidney-disease related gene in phatients with diabetic kidney disease. https://doi.org/10.1101/2020.05.18. 102822. Lee S, Abecasis GR, Boehnke M, Lin X (2014) Rarevariant association analysis: study designs and statistical tests. Am J Hum Genet 95:5–23 Li M, Pezzolesi MG (2018) Advances in understanding the genetic basis of diabetic kidney disease. Acta Diabetol 55:1093–1104 Macisaac RJ, Ekinci EI, Jerums G (2014) Markers of and risk factors for the development and progression of diabetic kidney disease. Am J Kidney Dis 63:S39–S62 Manolio TA, Collins FS, Cox NJ, Goldstein DB, Hindorff LA et al (2009) Finding the missing heritability of complex diseases. Nature 461:747–753 Martini S, Nair V, Patel SR, Eichinger F, Nelson RG et al (2013) From single nucleotide polymorphism to transcriptional mechanism: a model for FRMD3 in diabetic nephropathy. Diabetes 62:2605–2612

17

The Genetic Basis of Diabetic Kidney Disease

Palmer ND, Ng MC, Hicks PJ, Mudgal P, Langefeld CD, Freedman BI, Bowden DW (2014) Evaluation of candidate nephropathy susceptibility genes in a genomewide association study of African American diabetic kidney disease. PLoS One 9:e88273 Perkins BA, Ficociello LH, Roshan B, Warram JH, Krolewski AS (2010) In patients with type 1 diabetes and new-onset microalbuminuria the development of advanced chronic kidney disease may not require progression to proteinuria. Kidney Int 77:57–64 Pezzolesi MG, Katavetin P, Kure M, Poznik GD, Skupien J, Mychaleckyj JC, Rich SS, Warram JH, Krolewski AS (2009a) Confirmation of genetic associations at ELMO1 in the GoKinD collection supports its role as a susceptibility gene in diabetic nephropathy. Diabetes 58:2698–2702 Pezzolesi MG, Poznik GD, Mychaleckyj JC, Paterson AD, Barati MT et al (2009b) Genome-wide association scan for diabetic nephropathy susceptibility genes in type 1 diabetes. Diabetes 58:1403–1410 Quinn M, Angelico MC, Warram JH, Krolewski AS (1996) Familial factors determine the development of diabetic nephropathy in patients with IDDM. Diabetologia 39:940–945 Reidy K, Kang HM, Hostetter T, Susztak K (2014) Molecular mechanisms of diabetic kidney disease. J Clin Invest 124:2333–2340 Retnakaran R, Cull CA, Thorne KI, Adler AI, Holman RR (2006) Risk factors for renal dysfunction in type 2 diabetes: U.K. Prospective Diabetes Study 74. Diabetes 55:1832–1839 Reutens AT (2013) Epidemiology of diabetic kidney disease. Med Clin North Am 97:1–18 Roden DM, Mcleod HL, Relling MV, Williams MS, Mensah GA, Peterson JF, Van Driest SL (2019) Pharmacogenomics. Lancet 394:521–532 Salem RM, Todd JN, Sandholm N, Cole JB, Chen WM et al (2019) Genome-wide association study of diabetic kidney disease highlights biology involved in glomerular basement membrane collagen. J Am Soc Nephrol 30:2000–2016 Sambo F, Malovini A, Sandholm N, Stavarachi M, Forsblom C et al (2014) Novel genetic susceptibility loci for diabetic end-stage renal disease identified through robust naive Bayes classification. Diabetologia 57:1611–1622 Sandholm N, Salem RM, Mcknight AJ, Brennan EP, Forsblom C et al (2012) New susceptibility loci associated with kidney disease in type 1 diabetes. PLoS Genet 8:e1002921

235 Sandholm N, Forsblom C, Makinen VP, Mcknight AJ, Osterholm AM et al (2014) Genome-wide association study of urinary albumin excretion rate in patients with type 1 diabetes. Diabetologia 57:1143–1153 Sandholm N, Van Zuydam N, Ahlqvist E, Juliusdottir T, Deshmukh HA et al (2017) The genetic landscape of renal complications in type 1 diabetes. J Am Soc Nephrol 28:557–574 Seaquist ER, Goetz FC, Rich S, Barbosa J (1989) Familial clustering of diabetic kidney disease. Evidence for genetic susceptibility to diabetic nephropathy. N Engl J Med 320:1161–1165 Sharma SG, Bomback AS, Radhakrishnan J, Herlitz LC, Stokes MB, Markowitz GS, D’agati VD (2013) The modern spectrum of renal biopsy findings in patients with diabetes. Clin J Am Soc Nephrol 8:1718–1724 Sharma KR, Heckler K, Stoll SJ, Hillebrands JL, Kynast K et al (2016) ELMO1 protects renal structure and ultrafiltration in kidney development and under diabetic conditions. Sci Rep 6:37172 Shimazaki A, Kawamura Y, Kanazawa A, Sekine A, Saito S et al (2005) Genetic variations in the gene encoding ELMO1 are associated with susceptibility to diabetic nephropathy. Diabetes 54:1171–1178 Skupien J, Warram JH, Smiles AM, Niewczas MA, Gohda T, Pezzolesi MG, Cantarovich D, Stanton R, Krolewski AS (2012) The early decline in renal function in patients with type 1 diabetes and proteinuria predicts the risk of end-stage renal disease. Kidney Int 82:589–597 Taira M, Imamura M, Takahashi A, Kamatani Y, Yamauchi T et al (2018) A variant within the FTO confers susceptibility to diabetic nephropathy in Japanese patients with type 2 diabetes. PLoS One 13:e0208654 Teumer A, Tin A, Sorice R, Gorski M, Yeo NC et al (2016) Genome-wide association studies identify genetic loci associated with albuminuria in diabetes. Diabetes 65:803–817 Van Zuydam NR, Ahlqvist E, Sandholm N, Deshmukh H, Rayner NW et al (2018) A genome-wide association study of diabetic kidney disease in subjects with type 2 diabetes. Diabetes 67:1414–1427 Wang Y, Peng W, Zhang X, Qiao H, Wang L, Xu Z, Wu C (2016) The association of ACE gene polymorphism with diabetic kidney disease and renoprotective efficacy of valsartan. J Renin-Angiotensin-Aldosterone Syst 17:1470320316666749 Zhuo L, Ren W, Li W, Zou G, Lu J (2013) Evaluation of renal biopsies in type 2 diabetic patients with kidney disease: a clinicopathological study of 216 cases. Int Urol Nephrol 45:173–179

Epigenetics and Chronic Inflammation: Role in Early Detection of Type 2 Diabetes

18

Meenu Ghai

Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238 Metabolic Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238 Adipose Tissue Changes and Cytokine Expression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238 Chronic Inflammation and Insulin Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 Epigenetics of T2D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hyperglycemia and Epigenetics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Investigations in Twins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Epigenetic Wide Association Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

239 239 239 240

Noncoding RNA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 MicroRNAs in Type 2 Diabetes and Inflammation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241 Long Noncoding RNA in Type 2 Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241 Noncoding RNAs as Therapeutics Targets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241 High Fat Diet and Polyphenols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242 Beta Cell Dysfunction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242 Early Detection/Relative Risk Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242 Ongoing Clinical Trials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244

Abstract

Low-grade inflammation initiates even before type 2 diabetes (T2D) is diagnosed. As a response to change in inflammatory profile of cells and tissues, epigenetics modifications M. Ghai (*) Department of Genetics, School of Life Sciences, Westville Campus, University of Kwa-Zulu Natal, Durban, South Africa e-mail: [email protected]

such as DNA methylation (DNAm) and noncoding RNAs provide early cues about forthcoming discord in the bodily system. Thus, targeting epigenetic alterations that occur in the initial phases leading to T2D can provide therapeutics, which will prevent or halt the cascade of T2D and associated long-term complications. New biomarkers need to be identified for prediction and monitoring the progression of T2D. Early detection of

# Springer Nature Switzerland AG 2020 J. Faintuch and S. Faintuch (eds.), Obesity and Diabetes, https://doi.org/10.1007/978-3-030-53370-0_18

237

238

diabetes or prediabetes will also protect individuals from undesirable effects of chronic inflammation and metabolic memory. Keywords

Type 2 diabetes · Chronic inflammation · DNAm · Noncoding RNAs · Metabolic memory

Introduction The risk factors of type 2 diabetes (T2D) include genetic predisposition, age, and ethnicity; however, environmental factors should similarly be taken into account. T2D is characterized by hyperglycemia and combination of insulin resistance and/or insufficient insulin production by beta cells, which leads to metabolic derangements and widespread complications (Rawshani et al. 2017; Sladek 2018). Chronic inflammation plays a role in T2D, sometimes even before disease onset, even though it is not clinically prominent in most cases (Reddy et al. 2019; Tsalamandris et al. 2019). It is characterized by increased pro-inflammatory cytokines, histological changes, and immune shifts (Gregor and Hotamisligil 2011; Hotamisligil 2017). “Self“antigens can emerge and promote autoimmune activation. Insulin secretion and hyperglycemia can also be further impaired.

Fig. 18.1 Simplified depiction of development of chronic inflammation and “undesirable” metabolic memory in obesity and T2D. Epigenetic alterations provide early cues to metabolic imbalance and hence can be an ideal target for early detection of chronic inflammation in obesity and T2D

M. Ghai

Metabolic Memory Prolonged low-grade inflammation could mediate metabolic memory (Ceriello 2009; Testa et al. 2017) (Fig. 18.1). Intensive glycemic control is often recommended for the management of glucose homeostasis and microvascular complications (Holman et al. 2008; Gaede et al. 2008). Demonstrated genetic variants are not responsible for more than 10% of the heritable risk for T2D, while rare variants, gene–environment interactions, gene–gene interactions, and epigenetic factors (Kirchner et al. 2013) could be underestimated. Epigenetic mechanisms such as DNA methylation (DNAm) and noncoding RNAs regulate inflammatory gene expression and should deserve much attention (Naidoo et al. 2018).

Adipose Tissue Changes and Cytokine Expression Obesity leads to changes in tissue cell distribution and inflammatory activity, including pro-inflammatory cytokines and chemokines (Esser et al. 2014) (Fig. 18.1). Both subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) are associated with metabolic risk profile; however, the role of VAT is far more relevant (Kwon et al. 2017).

18

Epigenetics and Chronic Inflammation: Role in Early Detection of Type 2 Diabetes

Macrophages, mast cells, neutrophils, and T and B lymphocytes in VAT seem to be key players (Mraz and Haluzik 2014). Adipose tissue (AT) macrophages exhibit intense pro-inflammatory (M1) characteristics (Verboven et al. 2018). Macrophage activation in AT could precipitate insulin resistance (IR), along with M1 macrophage- or B-cell-mediated inflammation (Russo and Lumeng 2018), with little interference by subcutaneous fat (Verboven et al. 2018).

Chronic Inflammation and Insulin Resistance Chronic inflammation is associated with insulin resistance in the primary insulin target organs, mainly adipose tissue, muscle, and liver (Gregor and Hotamisligil 2011; Reilly and Saltiel 2017). Inflammatory cytokines compromise insulin signaling in adipocytes by inducing inflammatory pathways (Lee 2013). Dysregulation of preadipocyte/adipocyte functions promotes ectopic fat deposition and insulin resistance (Samuel and Shulman 2012; Wu and Ballantyne 2017). Communication between M1 and M2 macrophage polarizing is detected in this context, with predominance of the alternatively activated macrophage (M2) phenotype and activation of transcription molecules nuclear factor-kappa beta (NF-κB) and activator protein 1 (AP1). Insulin resistance-mediated epigenetic changes are recognized in monocytes and macrophages (Reddy et al. 2014; Hanson and Godfrey 2015).

239

TP53INP1, and ATP5G, was regulated by DNAm associated with genetic variants (Xue et al. 2018). Age, obesity, diet, physical activity, and fetal and early postnatal development are among the environmental drivers that should not be overlooked. Epigenetics modifications comprise DNAm, histone modification, and noncoding RNA, which regulate gene expression in a tissue specific manner. Environmental influences and DNA sequence variations or single nucleotide polymorphisms (SNPs), such as CpG-SNP, structural variations, and gene–gene interactions, also deserve to be mentioned.

Hyperglycemia and Epigenetics Hyperglycemia can induce a variety of epigenetic changes that can even persist after the normalization of glucose levels, mainly through the involvement of inflammatory genes (Reddy et al. 2015; Al-Haddad et al. 2016). Hyperglycemia can alter the activity of DNA methyltransferases (DNAmet), with irreversible changes over time. Epigenetic modifications may explain the long-term harmful effects of metabolic memory (Reddy et al. 2015). DNAm is a well-characterized epigenetic modification. Unlike genotypic variation, DNAm intensity patterns are liable to change over time, with age or following disease or other exposure. Naidoo et al. (2018) elaborately reviewed cell and tissue specific methylation changes associated with inflammation and T2D.

Investigations in Twins

Epigenetics of T2D At least 144 genetic variants (not completely independent) at 129 loci, identified by means of genome wide association studies (GWAS), are associated with T2D (Morris et al. 2012; Flannick and Florez 2016). Novel 39 common variants and 4 rare variants should be added (Xue et al. 2018). Gene expression of three genes, which play a role in T2D pathogenesis, namely, CAMK1D,

Monozygotic twins present an ideal model to study epigenetic contributions to the disease, as they are genetically the same and genetic influences on epigenetic variations can be ruled out. Because of tissue specificity of epigenetic regulation, it is essential to investigate a homogenous tissue or cell type from a target organ, which is influenced by alterations due to diabetes. RibelMadsen et al. (2012) investigated global DNAm

240

differences in skeletal muscle and subcutaneous adipose tissues from 12 monozygotic twins, discordant for type 2 diabetes. A total of 26,850 cytosine-guanine dinucleotide (CpG) sites in the promoters of 14,279 genes were analyzed. Small intratwin pair methylation differences between diabetic and nondiabetics occurred; however, promoters of genes PPARGC1A in muscle and HNF4A in adipose tissue showed increased methylation in type 2 diabetes. Increased expression of genes involved in inflammation and glycan degradation was observed in diabetes discordant monozygotic twins, with most differentially expressed genes being ELOVL6, GYS2, FADS1, SPP1 (OPN), CCL18, and IL1RN (Nilsson et al. 2014). Significant DNAm differences were modest; however, 1410 sites showed differential DNAm. Also 15,627 sites, representing 7046 genes including PPARG, KCNQ1, TCF7L2, and IRS1, showed differential DNAm in adipose tissue. Genome-wide methylated DNA immunoprecipitation sequencing (MeDIP-seq) in monozygotic twins reported hypermethylated DMRs in diabetic groups, with high hypermethylation in promoter of the MALT1 gene, involved in insulin and glycemic pathways and related to taurocholate levels in blood (Yuan et al. 2014). Liu et al. (2015) conducted bioinformatics analysis of DNAm differences in muscle tissues of monozygotic twins, observing 38 differentially methylated genes, including Sirtuin 1, N-acetyltransferase 6, phospholipase A2 group XIIB, and nuclear factor of activated T cell calcineurin-dependent 1. Hwang et al. (2018), reported ELOVL5 as an epigenetic biomarker for diabetes risk.

M. Ghai

body mass index (BMI) and one with waist circumference (WC), including sites in genes CPT1A, ABCG1, and SREBF1. Cross-tissue association study using adipose tissue DNA revealed wide agreement in BMI– and WC–methylation associations. Replication using blood DNA was similarly achieved for 37 BMI probes and one WC probe. Sixteen of these sites also replicated in adipose tissue, including 15 novel methylation findings near genes involved in lipid metabolism, immune response/cytokine signaling, and other diverse pathways, including LGALS3BP, KDM2B, PBX1, and BBS2, among others. Additional EWAS showing link between DNAm and T2D has also been reported (Yuan et al. 2014; Nilsson et al. 2014; Dayeh et al. 2014) In a recent study, Cardona et al. (2019) identified 15 novel methylation variable positions (MVPs) with significant associations with incident and prevalent T2D and also confirmed three previously identified MVPs. The study used whole blood DNA collected at baseline, up to 11 years before T2D onset, to investigate early epigenetic changes and their role in onset of T2D. The research was an incident T2D case-cohort study from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk cohort. Integration of genome –wide genetic data with methylation data revealed one MVP, cg00574958 at CPT1A, which could possibly play direct casual role in T2D. Interestingly, none of the genes with identified MVPs had been identified by genetic association studies, thus indicating use of novel mechanisms/ pathways for epigenetic alterations.

Noncoding RNA Epigenetic Wide Association Studies Epigenetic modifications can precede disease manifestation or occur as a result of disease diagnosis, and hence, prospective studies are better suited for studying casual changes. In the large epigenetic wide association study (EWAS) by Demerath et al. (2015), 37 variable methylation sites in leucocyte DNA were associated with

Noncoding RNAs do not translate into proteins but bring about epigenetic changes and function to regulate gene expression at the transcriptional and posttranscriptional level. Several microRNA (miRNA) and long noncoding RNA (lncRNA) have been implicated in beta cell development, insulin sensitivity/resistance, insulin production/ secretion, and insulin signaling. Noncoding RNAs are actively involved in early inflammation

18

Epigenetics and Chronic Inflammation: Role in Early Detection of Type 2 Diabetes

of the visceral adipose tissue and regulate inflammatory profiles of TNF-α, IL-1, IL-6, IL-18, intercellular adhesion molecule 1, VCAM-1, and plasminogen activator inhibitor 1 (Hamar 2012; Marques-Rocha et al. 2015).

241

are regulated in obesity and T2D. The study discovered 170 miRNA regulative elements in human adipose tissue and blood cells.

Long Noncoding RNA in Type 2 Diabetes MicroRNAs in Type 2 Diabetes and Inflammation miRNAs are linked with obesity and inflammation, either directly or indirectly (through regulatory elements such as transcription factors) (Arner and Kulyté 2015). Microarray analysis of human WAT tissues revealed several potentially relevant miRNAs (Heneghan et al. 2011; Keller et al. 2011; Arner and Kulyté 2015). To state few examples, miR-103 and miR-107 have been implicated in glucose homeostasis and insulin sensitivity (Trajkovski et al. 2011); miR-107 may also play a role in proinflammatory events (Foley and O’Neill 2012); miR-221 promotes white adipose tissue inflammation and decreases insulin sensitivity (Peng et al. 2018). miR 122 is implicated in liver steatosis and elevation in plasma cholesterol levels, circulating miR-122 is strongly associated with metabolic syndrome and T2D (Willeit et al. 2017), miR-146a expression is negatively correlated with fasting blood glucose (FBG), HbA1c, insulin resistance, proinflammatory signals such as TRAF6 and NFκβ mRNA levels, and also proinflammatory cytokines TNFα and IL-6 (Balasubramanyam et al. 2011), and finally, decreased serum level of miR-146a is a sign of chronic inflammation in T2D patients (Baldeón et al. 2014). A detailed literature survey by Yaribeygi et al. (2018) reports different noncoding microRNAs related to glucose metabolism and pathophysiology of T2D. The authors propose four mechanisms via which miRNAs may alter glucose metabolism: beta cell development, insulin sensitivity/resistance, insulin production/secretion, and insulin signaling. Gottmann et al. (2018) combined QTL, miRNA prediction, and transcriptomics to design a computational framework (miR-QTL-Scan) to identify miRNAs that

Human β-cell transcriptome analysis has shown dynamic regulation and abnormal expression of lncRNAs in T2D (Saeidi et al. 2018). A recent study addressed expression level of lncRNAs in peripheral blood mononuclear cells (PBMCs). Significantly increased levels of lncRNAs HOTAIR, MEG3, LET, MALAT1, MIAT, CDKN2BAS1/ANRIL, XIST, PANDA, GAS5, Linc-p21, ENST00000550337.1, PLUTO, and NBR2 were observed in T2D patients. lncRNA expression patterns of THRIL and SALRNA1 diminished in T2D. The majority of altered lncRNAs were positively correlated with poor glycemic control, insulin resistance, and transcriptional markers of senescence (Sathishkumar et al. 2018). Circulating lncRNA GAS5 less than 10 ng/μl was found to predict twelve times higher odds of having diabetes (Carter et al. 2015). Wang et al. (2017) identified 55 lncRNAs and 202 mRNAs to be differentially expressed in the blood samples from T2D group. miRNAs were mainly associated with immune regulation, inflammation, and insulin resistance. Newly emerged research interestingly indicates the use of exosomes miRNA and lncRNAs as potential biomarkers for detection or treatments of diabetes and diabetic complications (Chang and Wang 2019). Noncoding RNAs present an attractive target for T2D detection at early stages and may serve as clinical biomarkers.

Noncoding RNAs as Therapeutics Targets Several studies have reported the inhibition of miRNAs for therapeutic purposes (Nunez Lopez et al. 2016; Nigi et al. 2018; Jiménez-Lucena et al. 2018). Inhibition of miRNAs by antisense

242

oligonucleotides in mice models has proved to improve glucose homeostasis and insulin sensitivity. Inhibition of miR-103 and miR-107 by antisense oligonucleotides in liver and in adipose tissue of obese mice improved glucose homeostasis and insulin sensitivity. In contrast, injections in liver of an adenoviral vector expressing miR-107 resulted in elevated fasting blood glucose and insulin levels, impaired glucose tolerance, decreased insulin sensitivity, and increased hepatic glucose production (Trajkovski et al. 2011). Antisense oligonucleotides also demonstrated the potential therapeutic effects of liver-specific miR-122 inhibition and downregulation of miR-181a (Esau et al. 2006; Zhou et al. 2012). Lucia La Sala et al. (2019) demonstrated microRNA-21 as a biomarker for early detection of prediabetes and glucose imbalances. There was upregulation in impaired glucose tolerance ( IGT) and in T2D subjects. Inhibition of miR-200c and miR-21 has also been suggested against T2D (Geach 2015; Seeger et al. 2014). Tissue-specific miR-199a-3p and miR-223 are potential tissue biomarkers for pancreas and liver, respectively, in the context of T2D (Zhu and Leung 2015).

High Fat Diet and Polyphenols Dietary modifications have also been shown to indirectly modulate miRNA expression (Parra et al. 2010). Experimental high fat diet increased the expression of miR-103 and miR-107, with reversal by plant-derived polyphenols. Dietary polyphenols fed with high fat diet also decreased the expression of miR-122, reduced weight gain, liver steatosis, and insulin resistance (Joven et al. 2012).

Beta Cell Dysfunction In the relationship between Insulin sensitivity and Cardiovascular disease (RISC) cohort, biomarkers of IGT/reduced β-cell glucose

M. Ghai

sensitivity were mainly adiponectin, alpha-1antitrypsin (known to regulate adiponectin levels), endocan, miR-181a, miR-342, and miR-323. The proteins identified were adiponectin, endocan, and sialoadhesin (Belongie et al. 2017). Despite success in animal models, techniques for in vivo specific delivery of “therapeutic” miRNAs will need to be tested and optimized, in order to restore physiological levels of a miRNA deregulated in a specific tissue. miRNA combination therapy could be necessary to address multiple dysregulated miRNAs associated with T2D.

Early Detection/Relative Risk Tests The International Diabetes Federation (IDF) has estimated that among 642 million cases by 2040, half of them will not be diagnosed (Ogurtsova et al. 2017). Early detection tests/screening of the general population are very important to facilitate risk identification and to curb the damage at early stages. Selective or targeted screening of T2D is performed in high risk cohorts selected by age, body weight, or ethnic origin. Opportunistic screening is conducted by health care professionals, for any other reason, during routine appointments. The most useful glucose homeostasis test is still debated (Vatandoost et al. 2015). According to Barry et al. (2017), glycated hemoglobin A1c (HbA1c) was neither sensitive nor specific for prediabetes; fasting glucose was specific however not sensitive. Divergence between the criteria of the American Diabetes Association and WHO leads to identification of different populations with limited overlap. The study also suggested that “screen and treat” policies alone are unlikely to halt the epidemic of type 2 diabetes. In the experience of Laiteerapong et al. (2019), newly diagnosed diabetes and an unstable initial 10-year HbA1c predisposed to microvascular complications, even after adjusting for HbA1c control in year 1. Repeated measurements of fasting plasma glucose seem to better predict diabetes than a single

18

Epigenetics and Chronic Inflammation: Role in Early Detection of Type 2 Diabetes

243

Table 18.1 List of ongoing clinical trials on T2D and epigenetics

Type of study Observational/ prospective

Stage/ No. of participants Recruiting N ¼240

observational / Case control/ prospective

Not yet Recruiting N ¼100

Sex-specific Relationship of Epigenetic-Based Modifications in the Saliva and Blood With the Occurrence of Type 2 Diabetes

Observational/ Prospective

Recruiting N ¼224

Unravelling the Role of Mitochondrial DNA Methylation in Type 2 Diabetes

Observational/ Prospective

Recruiting N¼36

Impact of Metabolic Health on Sperm Epigenetic Marks in Humans.

Interventional/ Nonrandomized

Recruiting N ¼40

Perturbation of Interactome Through MicroRNA And Methylome Analyses In Diabetes Endophenotypes: the PIRAMIDE Study Design

Observational/ case-control/ Prospective

Recruiting N ¼35

Investigating the Underlying Mechanisms of Exercise Resistance in Individuals With Type 2 Diabetes

Interventional/ nonrandomized.

Active N¼33

The Interaction Between Protein Intake, Gut Microbiota, and Type 2 Diabetes in Subjects With Different Ethnic Backgrounds (MICRODIET)

Interventional/ Randomized

Recruiting N ¼120

Title of the study Epigenetic Contribution to the Pathogenesis of Diabetic Nephropathy in Qatari Population Network-based EpigenomeWide association Study in Obesity precision Medicine: NEWTON Clinical Trial

Major outcomes( epigenetics) Assessment of DNA methylation in monocytes, Assessment of urinary microRNAs (a) A disease module containing the crucial differentially methylated genes in obese patients and obese patients with T2D compared to controls. (b) Identification of differentially expressed microRNA and mRNA Correlation of miRNAs in the saliva with the amount of intrahepatic liver fat, ectopic lipids in the heart, and skeletal muscle. Mitochondrial DNA methylation and D-loop changes in insulin resistant states such as obesity and type 2 diabetes Changes in epigenetic markers (DNA methylation and noncoding RNAs) in overweight men with type 1 or type 2 diabetes with a 3 month lifestyle intervention program. (a) Identification of differentially methylated genes in both CD4+ and CD8+ cells from T2D patients and controls. (b) Identification of differentially expressed microRNA and mRNA target in both CD4+ and CD8+ cells isolated from T2D patients and controls. (c) Putative epigenetics interactions in the presence or absence of T2D-related cardiovascular dysfunction. Relationship between the basal promoter methylation status of key genes involved in fuel metabolism and activated by exercise in skeletal muscle tissue and cells. Epigenetic modifications in monocytes of patients at baseline and end of dietary intervention

Location (Country) Qatar

Italy

Austria

United States

United States

Italy

United States

France

(continued)

244

M. Ghai

Table 18.1 (continued) Stage/ No. of participants Recruiting N ¼210

Title of the study Who Will Benefit From Bariatric Surgery for Diabetes? Using Fat Distribution Measurement, Gut Hormone Profiles, and Genetic Data to Predict Diabetes Remission Consequences of Hypoglycemia on Cardiovascular and Inflammatory Responses (HCIR)

Type of study Observational/ prospective

Interventional, nonrandomized, clinical trial

Recruiting N ¼112

Association Between Urinary and Serum Levels of miRNA 192 and miRNA 25 and Glomerular Filtration and Albuminuria in Patients With and Without Type 2 Diabetes. Prognostic Predictors of Response to Hypoglycemic Therapy

Observational/ retrospective

Recruiting N ¼300

Interventional, randomized

Recruiting N ¼800

test (Inoue et al. 2012). In the opinion of Jackson et al. (2017), a 50-g oral glucose followed by 1-h glucose measurement is superior to other screening tests. If abnormal, an oral glucose tolerance test could follow. Such strategy could be cost effective in high risk populations. Feldman et al. (2017) were able to diagnose diabetes 4.6 years earlier, by screening asymptomatic individuals, and these cases had a more favorable clinical course than clinically detected diabetes after diagnosis. Screening for both T2D and prediabetes should begin at age 45–50, with follow-up every 5 years, and targeted screening appears to be more cost-effective compared to routine evaluation (Einarson et al. 2017).

Ongoing Clinical Trials Table 18.1 depicts a few ongoing clinical trials on T2D and epigenetics. The recent research will accelerate the interventions into clinical practice and improve early detection of T2D and arrest of associated complications.

Major outcomes( epigenetics) Epigenetic changes in visceral adipose tissue of T2D patients on mixed meal remission, who underwent Roux-en-Y gastric bypass surgery Epigenetic modifications due to hypoglycemia in the promoter regions of the pro-inflammatory cytokines in monocytes Urine and serum expression of miRNA192 and miRNA 25

Serum level of microRNA-126, microRNA-21, microRNA-27, miRNA-125, and miRoRNA-155 from baseline to 6 and 12 months after intervention

Location (Country) United Kingdom

Netherlands

Italy

Russia

References Al-Haddad R, Karnib N, Assaad RA et al (2016) Epigenetic changes in diabetes. Neurosci Lett 625:64–69. https://doi.org/10.1016/j.neulet.2016.04.046 Arner P, Kulyté A (2015) MicroRNA regulatory networks in human adipose tissue and obesity. Nat Rev Endocrinol 11(5):276–288. https://doi.org/10.1038/ nrendo.2015.25 Balasubramanyam M, Aravind S, Gokulakrishnan K et al (2011) Impaired miR-146a expression links subclinical inflammation and insulin resistance in Type 2 diabetes. Mol Cell Biochem 351(1–2):197–205. https://doi.org/ 10.1007/s11010-011-0727-3 Baldeón RL, Weigelt K, de Wit H et al (2014) Decreased serum level of miR-146a as sign of chronic inflammation in type 2 diabetic patients. PLoS One 9(12): e115209. https://doi.org/10.1371/journal.pone. 0115209 Barry E, Roberts S, Oke J, Vijayaraghavan S, Normansell R, Greenhalgh T (2017) Efficacy and effectiveness of screen and treat policies in prevention of type 2 diabetes: systematic review and meta-analysis of screening tests and interventions. BMJ 356:i6538. https://doi.org/10.1136/bmj.i6538 Belongie KJ, Ferrannini E, Johnson K, Andrade-Gordon P, Hansen MK, Petrie JR, Wagner B (2017) Identification of novel biomarkers to monitor β-cell function and

18

Epigenetics and Chronic Inflammation: Role in Early Detection of Type 2 Diabetes

enable early detection of type 2 diabetes risk. PLoS One 12(8):e0182932 Cardona A, Day FR, Perry JRB et al (2019) Epigenomewide association study of incident type 2 diabetes in a British population: EPIC-Norfolk Study. Diabetes 68 (12):2315–2326. https://doi.org/10.2337/db18-0290 Carter G, Miladinovic B, Patel AA, Deland L, Mastorides S, Patel NA (2015) Circulating long noncoding RNA GAS5 levels are correlated to prevalence of type 2 diabetes mellitus. BBA Clin 4:102–107. https://doi.org/10.1016/j.bbacli.2015.09.001 Chang W, Wang J (2019) Exosomes and their noncoding RNA cargo are emerging as new modulators for diabetes mellitus. Cells 8(8):853 Ceriello A (2009) Hypothesis: the “metabolic memory”, the new challenge of diabetes. Diabetes Res Clin Pract 86(Suppl 1):S2–S6. https://doi.org/10.1016/S01688227(09)70002-6 Dayeh T, Volkov P, Salö S et al (2014) Genome-wide DNAm analysis of human pancreatic islets from type 2 diabetic and non-diabetic donors identifies candidate genes that influence insulin secretion. PLoS Genet 10 (3):e1004160. https://doi.org/10.1371/journal.pgen. 1004160 Demerath EW, Guan W, Grove ML et al (2015) Epigenome-wide association study (EWAS) of BMI, BMI change and waist circumference in African American adults identifies multiple replicated loci. Hum Mol Genet 24(15):4464–4479. https://doi.org/10.1093/ hmg/ddv161 Einarson TR, Bereza BG, Acs A, Jensen R (2017) Systematic literature review of the health economic implications of early detection by screening populations at risk for type 2 diabetes. Curr Med Res Opin 33(2):331–358. https://doi.org/10.1080/ 03007995.2016.1257977 Esau C, Davis S, Murray SF et al (2006) miR-122 regulation of lipid metabolism revealed by in vivo antisense targeting. Cell Metab 3(2):87–98. https://doi.org/10. 1016/j.cmet.2006.01.005 Esser N, Legrand-Poels S, Piette J, Scheen AJ, Paquot N (2014) Inflammation as a link between obesity, metabolic syndrome and type 2 diabetes. Diabetes Res Clin Pract 105(2):141–150. https://doi.org/10.1016/j. diabres.2014.04.006 Feldman AL, Griffin SJ, Fhärm E et al (2017) Screening for type 2 diabetes: do screen-detected cases fare better? Diabetologia 60(11):2200–2209. https://doi.org/ 10.1007/s00125-017-4402-4 Flannick J, Florez JC (2016) Type 2 diabetes: genetic data sharing to advance complex disease research. Nat Rev Genet 17(9):535–549. https://doi.org/10.1038/nrg. 2016.56 Foley NH, O’Neill LA (2012) miR-107: a toll-like receptor-regulated miRNA dysregulated in obesity and type II diabetes. J Leukoc Biol 92(3):521–527. https://doi. org/10.1189/jlb.0312160

245

Gaede P, Lund-Andersen H, Parving HH, Pedersen O (2008) Effect of a multifactorial intervention on mortality in type 2 diabetes. N Engl J Med 358 (6):580–591. https://doi.org/10.1056/ NEJMoa0706245 Geach T (2015) Preventing β-cell apoptosis and T2D with microRNAs—a role for miR-200? Nat Rev Endocrinol 11(8):444. https://doi.org/10.1038/nrendo.2015.92 Gottmann P, Ouni M, Saussenthaler S et al (2018) A computational biology approach of a genome-wide screen connected miRNAs to obesity and type 2 diabetes. Mol Metab 11:145–159. https://doi.org/10.1016/j. molmet.2018.03.005 Gregor MF, Hotamisligil GS (2011) Inflammatory mechanisms in obesity. Annu Rev Immunol 29:415–445. https://doi.org/10.1146/annurevimmunol-031210-101322 Hamar P (2012) Role of regulatory micro RNAs in type 2 diabetes mellitus-related inflammation. Nucleic Acid Ther 22(5):289–294. https://doi.org/10.1089/nat.2012. 0381 Hanson MA, Godfrey KM (2015) Genetics: epigenetic mechanisms underlying type 2 diabetes mellitus. Nat Rev Endocrinol 11(5):261–262. https://doi.org/10. 1038/nrendo.2015.31 Heneghan HM, Miller N, McAnena OJ, O’Brien T, Kerin MJ (2011) Differential miRNA expression in omental adipose tissue and in the circulation of obese patients identifies novel metabolic biomarkers. J Clin Endocrinol Metab 96(5):E846–E850. https://doi.org/ 10.1210/jc.2010-2701 Holman RR, Paul SK, Bethel MA, Neil HA, Matthews DR (2008) Long-term follow-up after tight control of blood pressure in type 2 diabetes. N Engl J Med 359 (15):1565–1576. https://doi.org/10.1056/ NEJMoa0806359 Hotamisligil GS (2017) Inflammation, metaflammation and immunometabolic disorders. Nature 542 (7640):177–185. https://doi.org/10.1038/nature21363 Hwang JY, Lee HJ, Go MJ et al (2018) Genome-wide methylation analysis identifies ELOVL5 as an epigenetic biomarker for the risk of type 2 diabetes mellitus. Sci Rep 8(1):14862. https://doi.org/10.1038/s41598018-33238-9 Inoue K, Inoue M, Matsumoto M, Akimoto K (2012) Persistent fasting hyperglycaemia is more predictive of type 2 diabetes than transient fasting hyperglycaemia. Diabet Med 29(7):e75–e81. https:// doi.org/10.1111/j.1464-5491.2011.03536.x Jackson SL, Safo SE, Staimez LR et al (2017) Glucose challenge test screening for prediabetes and early diabetes. Diabet Med 34(5):716–724. https://doi.org/10. 1111/dme.13270 Jiménez-Lucena R, Camargo A, Alcalá-Diaz JF et al (2018) A plasma circulating miRNAs profile predicts type 2 diabetes mellitus and prediabetes: from the CORDIOPREV study. Exp Mol Med 50(12):168. https://doi.org/10.1038/s12276-018-0194-y

246 Joven J, Espinel E, Rull A et al (2012) Plant-derived polyphenols regulate expression of miRNA paralogs miR-103/107 and miR-122 and prevent diet-induced fatty liver disease in hyperlipidemic mice. Biochim Biophys Acta 1820(7):894–899. https://doi.org/10. 1016/j.bbagen.2012.03.020 Keller P, Gburcik V, Petrovic N et al (2011) Gene-chip studies of adipogenesis-regulated microRNAs in mouse primary adipocytes and human obesity. BMC Endocr Disord 11:7. https://doi.org/10.1186/14726823-11-7 Kirchner H, Osler ME, Krook A, Zierath JR (2013) Epigenetic flexibility in metabolic regulation: disease cause and prevention? Trends Cell Biol 23(5):203–209. https://doi.org/10.1016/j.tcb.2012.11.008 Kwon H, Kim D, Kim JS (2017) Body fat distribution and the risk of incident metabolic syndrome: a Longitudinal Cohort Study. Sci Rep 7(1):10955. https://doi.org/ 10.1038/s41598-017-09723-y La Sala L, Mrakic-Sposta S, Tagliabue E et al (2019) Circulating microRNA-21 is an early predictor of ROS-mediated damage in subjects with high risk of developing diabetes and in drug-naïve T2D. Cardiovasc Diabetol 18(1):18. https://doi.org/10. 1186/s12933-019-0824-2 Laiteerapong N, Ham SA, Gao Y et al (2019) The legacy effect in type 2 diabetes: impact of early glycemic control on future complications (the diabetes & aging study). Diabetes Care 42(3):416–426. https://doi.org/ 10.2337/dc17-1144 Liu F, Sun Q, Wang L, Nie S, Li J (2015) Bioinformatics analysis of abnormal DNA methylation in muscle samples from monozygotic twins discordant for type 2 diabetes. Mol Med Rep 12(1):351–356. https://doi. org/10.3892/mmr.2015.3452 Lee J (2013) Adipose tissue macrophages in the development of obesity-induced inflammation, insulin resistance and type 2 diabetes. Arch Pharm Res 36 (2):208–222. https://doi.org/10.1007/s12272-0130023-8 Marques-Rocha JL, Samblas M, Milagro FI, Bressan J, Martínez JA, Marti A (2015) Noncoding RNAs, cytokines, and inflammation-related diseases. FASEB J 29(9):3595–3611. https://doi.org/10.1096/fj.14260323 Morris AP, Voight BF, Teslovich TM et al (2012) Largescale association analysis provides insights into the genetic architecture and pathophysiology of type 2 diabetes. Nat Genet 44(9):981–990. https://doi.org/10. 1038/ng.2383 Mraz M, Haluzik M (2014) The role of adipose tissue immune cells in obesity and low-grade inflammation. J Endocrinol 222(3):R113–R127. https://doi.org/10. 1530/JOE-14-0283 Naidoo V, Naidoo M, Ghai M (2018) Cell- and tissuespecific epigenetic changes associated with chronic inflammation in insulin resistance and type 2 diabetes mellitus. Scand J Immunol 88(6):e12723. https://doi. org/10.1111/sji.12723

M. Ghai Nigi L, Grieco GE, Ventriglia G et al (2018) MicroRNAs as regulators of insulin signaling: research updates and potential therapeutic perspectives in type 2 diabetes. Int J Mol Sci 19(12):3705. https://doi.org/10.3390/ ijms19123705 Nilsson E, Jansson PA, Perfilyev A et al (2014) Altered DNAm and differential expression of genes influencing metabolism and inflammation in adipose tissue from subjects with type 2 diabetes. Diabetes 63 (9):2962–2976. https://doi.org/10.2337/db13-1459 Nunez Lopez YO, Garufi G, Seyhan AA (2016) Altered levels of circulating cytokines and microRNAs in lean and obese individuals with prediabetes and type 2 diabetes. Mol BioSyst 13(1):106–121. https://doi.org/10. 1039/c6mb00596a Ogurtsova K, da Rocha Fernandes JD, Huang Y et al (2017) IDF diabetes atlas: global estimates for the prevalence of diabetes for 2015 and 2040. Diabetes Res Clin Pract 128(6):40–50. https://doi.org/10.1016/ j.diabres.2017.03.024 Parra P, Serra F, Palou A (2010) Expression of adipose microRNAs is sensitive to dietary conjugated linoleic acid treatment in mice. PLoS One 5(9):e13005. https:// doi.org/10.1371/journal.pone.0013005 Peng J, Zhou Y, Deng Z et al (2018) miR-221 negatively regulates inflammation and insulin sensitivity in white adipose tissue by repression of sirtuin-1 (SIRT1). J Cell Biochem 119(8):6418–6428. https://doi.org/10. 1002/jcb.26589 Rawshani A, Rawshani A, Franzén S et al (2017) Mortality and cardiovascular disease in type 1 and type 2 diabetes. N Engl J Med 376(15):1407–1418. https://doi. org/10.1056/NEJMoa1608664 Reddy MA, Chen Z, Park JT et al (2014) Regulation of inflammatory phenotype in macrophages by a diabetesinduced long noncoding RNA. Diabetes 63 (12):4249–4261. https://doi.org/10.2337/db14-0298 Reddy MA, Zhang E, Natarajan R (2015) Epigenetic mechanisms in diabetic complications and metabolic memory. Diabetologia 58(3):443–455. https://doi.org/ 10.1007/s00125-014-3462-y Reddy P, Lent-Schochet D, Ramakrishnan N, McLaughlin M, Jialal I (2019) Metabolic syndrome is an inflammatory disorder: A conspiracy between adipose tissue and phagocytes. Clin Chim Acta 496:35–44. https://doi.org/10.1016/j.cca.2019.06.019 Reilly SM, Saltiel AR (2017) Adapting to obesity with adipose tissue inflammation. Nat Rev Endocrinol 13 (11):633–643. https://doi.org/10.1038/nrendo.2017.90 Ribel-Madsen R, Fraga MF, Jacobsen S et al (2012) Genome-wide analysis of DNAm differences in muscle and fat from monozygotic twins discordant for type 2 diabetes. PLoS One 7(12):e51302. https://doi.org/10. 1371/journal.pone.0051302 Russo L, Lumeng CN (2018) Properties and functions of adipose tissue macrophages in obesity. Immunology 155(4):407–417. https://doi.org/10.1111/imm.13002 Saeidi L, Ghaedi H, Sadatamini M et al (2018) Long non-coding RNA LY86-AS1 and HCG27_201

18

Epigenetics and Chronic Inflammation: Role in Early Detection of Type 2 Diabetes

expression in type 2 diabetes mellitus. Mol Biol Rep 45 (6):2601–2608. https://doi.org/10.1007/s11033-0184429-8 Samuel VT, Shulman GI (2012) Mechanisms for insulin resistance: common threads and missing links. Cell 148(5):852–871. https://doi.org/10.1016/j.cell.2012. 02.017 Sathishkumar C, Prabu P, Mohan V, Balasubramanyam M (2018) Linking a role of lncRNAs (long non-coding RNAs) with insulin resistance, accelerated senescence, and inflammation in patients with type 2 diabetes. Hum Genomics 12(1):41. https://doi.org/10.1186/s40246018-0173-3 Seeger T, Fischer A, Muhly-Reinholz M, Zeiher AM, Dimmeler S (2014) Long-term inhibition of miR-21 leads to reduction of obesity in db/db mice. Obesity (Silver Spring) 22(11):2352–2360. https://doi.org/10. 1002/oby.20852 Sladek R (2018) The many faces of diabetes: addressing heterogeneity of a complex disease. Lancet Diabetes Endocrinol 6(5):348–349. https://doi.org/10.1016/ S2213-8587(18)30070-6 Testa R, Bonfigli AR, Prattichizzo F, La Sala L, De Nigris V, Ceriello A (2017) The “metabolic memory” theory and the early treatment of hyperglycemia in prevention of diabetic complications. Nutrients 9 (5):437. https://doi.org/10.3390/nu9050437 Trajkovski M, Hausser J, Soutschek J et al (2011) MicroRNAs 103 and 107 regulate insulin sensitivity. Nature 474(7353):649–653. https://doi.org/10.1038/ nature10112 Tsalamandris S, Antonopoulos AS, Oikonomou E et al (2019) The role of inflammation in diabetes: current concepts and future perspectives. Eur Cardiol 14 (1):50–59. https://doi.org/10.15420/ecr.2018.33.1 Vatandoost N, Amini M, Iraj B, Momenzadeh S, Salehi R (2015) Dysregulated miR-103 and miR-143 expression in peripheral blood mononuclear cells from induced prediabetes and type 2 diabetes rats. Gene 572 (1):95–100. https://doi.org/10.1016/j.gene.2015.07.015 Verboven K, Wouters K, Gaens K et al (2018) Abdominal subcutaneous and visceral adipocyte size, lipolysis and

247

inflammation relate to insulin resistance in male obese humans. Sci Rep 8(1):4677. https://doi.org/10.1038/ s41598-018-22962-x Wang X, Chang X, Zhang P, Fan L, Zhou T, Sun K (2017) Aberrant expression of long non-coding RNAs in newly diagnosed type 2 diabetes indicates potential roles in chronic inflammation and insulin resistance. Cell Physiol Biochem 43(6):2367–2378. https://doi. org/10.1159/000484388 Willeit P, Skroblin P, Moschen AR et al (2017) Circulating microRNA-122 Is associated with the risk of new-onset metabolic syndrome and type 2 diabetes. Diabetes 66(2):347–357. https://doi.org/10.2337/ db16-0731 Wu H, Ballantyne CM (2017) Skeletal muscle inflammation and insulin resistance in obesity. J Clin Invest 127 (1):43–54. https://doi.org/10.1172/JCI88880 Xue A, Wu Y, Zhu Z et al (2018) Genome-wide association analyses identify 143 risk variants and putative regulatory mechanisms for type 2 diabetes. Nat Commun 9(1):2941. https://doi.org/10.1038/s41467018-04951-w Yaribeygi H, Katsiki N, Behnam B, Iranpanah H, Sahebkar A (2018) MicroRNAs and type 2 diabetes mellitus: Molecular mechanisms and the effect of antidiabetic drug treatment. Metabolism 87:48–55. https://doi.org/10.1016/j.metabol.2018.07.001 Yuan W, Xia Y, Bell CG et al (2014) An integrated epigenomic analysis for type 2 diabetes susceptibility loci in monozygotic twins. Nat Commun 5:5719. https://doi.org/10.1038/ncomms6719 Zhou B, Li C, Qi W et al (2012) Downregulation of miR-181a upregulates sirtuin-1 (SIRT1) and improves hepatic insulin sensitivity. Diabetologia 55 (7):2032–2043. https://doi.org/10.1007/s00125-0122539-8 Zhu H, Leung SW (2015) Identification of microRNA biomarkers in type 2 diabetes: a meta-analysis of controlled profiling studies. Diabetologia 58(5):900–911. https://doi.org/10.1007/s00125-015-3510-2B62

Salivary and Urinary Metabolome in Pediatric Obesity and Metabolic Syndrome

19

Jacopo Troisi, Francesca Marciano, Giovanni Scala, Elizabeth Plunk, Luca Pierri, and Angelo Colucci

Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 Metabolic Features of Pediatric Obesity and MetS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251 Urine and Salivary Pathways and Biomolecules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253 Saliva Production . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253 Urine Production . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253 Salivary and Urinary Metabolome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Salivary Metabolome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Urinary Metabolome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Small Intestinal Bacterial Overgrowth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

254 254 255 257

Potential Targets for New Drug Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 Phytotherapeutic Agents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 Gut Microbiota Interventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 Ongoing Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260

J. Troisi (*) Department of Medicine and Surgery and Dentistry, “Scuola Medica Salernitana”, University of Salerno, Salerno, Italy Theoreo srl—Spin-Off Company of the University of Salerno, Salerno, Italy European Biomedical Research Institute of Salerno (EBRIS), Salerno, Italy e-mail: [email protected] F. Marciano European Biomedical Research Institute of Salerno (EBRIS), Salerno, Italy G. Scala Theoreo srl—Spin-Off Company of the University of Salerno, Salerno, Italy Hosmotic srl, Vico Equense, Italy

E. Plunk Department of Biological and Environmental Sciences, University of Tennessee-Chattanooga, Chattanooga, TN, USA L. Pierri Department of Translational Medical Sciences, Section of Pediatrics, University of Naples Federico II, Naples, Italy A. Colucci Department of Medicine and Surgery and Dentistry, “Scuola Medica Salernitana”, University of Salerno, Salerno, Italy

# Springer Nature Switzerland AG 2020 J. Faintuch and S. Faintuch (eds.), Obesity and Diabetes, https://doi.org/10.1007/978-3-030-53370-0_19

249

250

Abstract

Childhood obesity is reaching alarming rates in many countries, posing an urgent and serious challenge. Adipose tissue is a key endocrine organ that releases several pro- or antiinflammatory adipokines that are involved in the pathogenesis of obesity complications. Moreover, it is suggested that gut microbiota is also involved in the development of these complications, including obesity-related liver disease and metabolic syndrome. Metabolomics has recently started to pave the way to a better pathomechanistic understanding of hepatometabolic complications, leading to a more efficient diagnosis and better therapeutic approaches. Several metabolites and metabolic pathways contribute to a complex metabolic fingerprint of obesity, metabolic syndrome, and obesity-related non-alcoholic fatty liver disease (NAFLD). Indeed, these conditions seem to have different salivary and urinary metabolomic signatures. The aim of this chapter is to provide an overview of these signatures, metabolomic-driven findings, and perspectives for obesity and obesity-related condition diagnoses and treatments. Keywords

Pediatric obesity · metabolic syndrome · nonalcoholic fatty liver disease · metabolomics

Introduction Obese children and adolescents are at high risk of developing several metabolic disorders that were previously considered to be “adult” diseases, including insulin resistance (IR), metabolic syndrome (MetS), type-2 diabetes mellitus (T2DB), hypertension, dyslipidemia, obstructive sleep apnea (OSA), and non-alcoholic fatty liver disease (NAFLD) (Kumar and Kelly 2017; WHO 2016; Morales Camacho et al. 2019; Dietz and Robinson 2005; Lakshman et al. 2012). This is the first time in human history that we are meeting

J. Troisi et al.

these phenomena in pediatric populations, and the effects on subsequent adulthood are not easily predictable (Rosenbaum 2018). Adipose tissue is a key endocrine organ that releases several pro- or anti-inflammatory adipokines, which are involved in the pathogenesis of obesity complications. Moreover, it is suggested that gut microbiota is also involved in the development of these complications, including obesity-related liver disease and obesity itself (Vajro et al. 2013a). NAFLD is a clinical–pathological condition characterized by abnormal lipid deposition in hepatocytes in the absence of excess alcohol intake. It includes a disease spectrum ranging from isolated hepatic steatosis to more severe forms (Non-alcoholic Steatohepatitis, NASH) with inflammation, liver fibrosis, cirrhosis, and eventually hepatocellular carcinoma (HCC) (Tiniakos et al. 2010). The majority of patients with NAFLD are obese: the obesity-related chronic mild systemic inflammation blocks insulin signaling pathways and leads to insulin resistance, which plays a likely role in the liver disease pathomechanism (Sanyal et al. 2001; Fabbrini et al. 2010). NAFLD is now considered as the hepatic manifestation of MetS,(Abenavoli et al. 2017; Buzzetti et al. 2016) that is essentially characterized by the clustering of metabolic abnormalities such as glucose intolerance, obesity, dyslipidemia, and hypertension (Hosseinpour-Niazi et al. 2019; Bussler et al. 2017). While the pathogenesis of MetS and the role of each of its components is complex and not completely elucidated (Fig. 19.1), abdominal obesity and insulin resistance are considered important causative factors (Alberti et al. 2006). The International Diabetes Federation (IDF) provided the Worldwide Consensus definition of MetS, identifying abdominal obesity (defined as waist circumference) as a prerequisite of MetS (Alberti et al. 2006; Zimmet et al. 2007). In addition, diagnosis is defined by the presence of at least two of the following features: high blood triglycerides (TG), reduced HDL cholesterol

19

Salivary and Urinary Metabolome in Pediatric Obesity and Metabolic Syndrome

251

Fig. 19.1 Pathophysiological changes related to insulin resistance in various organs

(HDL-C), increased blood pressure, or increased fasting blood glucose (FBG) (Zafar et al. 2018). Although there is no agreement on a MetS definition for children and adolescents (Bussler et al. 2017), prevalence is approximately 30%. A current MetS definition in pediatric population is based on the presence of 3 or more of following criteria: (1) TG
110 mg/dL or (WHO 2016); HDL-C 85th) or obesity (BMI > 95th) conditions; adherence to the study and signature of informed consent. The exclusion criteria are history of chronic or acute not obesity-related diseases, and/or pathologies that do not allow saliva collection. Other ongoing studies include Science and Technology in childhood Obesity Policy (STOP) (2019) the EPHORT Childhood Obesity Project (2016), and Childhood Obesity Research Demonstration (CORD) 3.0. (2019) STOP is working to identify policy changes that will address childhood obesity across Europe, until May 2022. It will assess from before birth through childhood, the key components of becoming obese, while putting emphasis on vulnerable and socially disadvantaged children. The goal is to have effective and sustainable solutions for childhood obesity to be implemented in the EU.

260

The EPHORT Childhood Obesity Project is taking place from 2014 to 2020. Eight areas of action have been identified: (1) Support a healthy start in life, (2) Promote healthier environments, especially in schools and pre-schools, (3) Make the healthy option the easier option, (4) Restrict marketing and advertising to children, (5) Inform and empower families, (6) Encourage physical activity, (7) Monitor and evaluate, and (8) Increase research. The first task for this project was to identify the prevalence of obesity per country in the EU. Then referring to the Areas of Actions, policies, and activities were made. After this, each country was evaluated to see if the actions had been taken, and the prevalence of obesity was measured. Task three included an overview of the engagement of the relevant states, the Commission, and the international organizations. Once this was complete the team is proceeding to assess the Action Plan and make recommendations for the second half-period. CORD 3.0 will be funded by Massachusetts General Hospital, The Miriam Hospital, Stanford University, University of Nebraska, and Washington University in St. Louis from 2019 to 2024. The goal of the project is for these five research teams to focus on adapting, testing, and packaging effective programs to reduce childhood obesity among children in lower-income families.

References Abenavoli L, Greco M, Milic N et al (2017) Effect of Mediterranean diet and antioxidant formulation in non-alcoholic fatty liver disease: a randomized study. Nutrients 9(8):870 Alberti KGMM, Zimmet P, Shaw J (2006) Metabolic syndrome—a new world-wide definition. A consensus statement from the international diabetes federation. Diabet Med 23(5):469–480 de Almeida PDV, Gregio AM, Machado MA, De Lima AA, Azevedo LR (2008) Saliva composition and functions: a comprehensive review. J Contemp Dent Pract 9(3):72–80 Amo K, Arai H, Uebanso T et al (2011) Effects of xylitol on metabolic parameters and visceral fat accumulation. J Clin Biochem Nutr 49:1106150086 Aristizabal JC, Barona J, Gonzalez-Zapata LI, Deossa GC, Estrada A (2016) Fatty acid content of plasma triglycerides may contribute to the heterogeneity in

J. Troisi et al. the relationship between abdominal obesity and the metabolic syndrome. Metab Syndr Relat Disord 14 (6):311–317 Badoud F, Lam KP, Perreault M, Zulyniak MA, BritzMcKibbin P, Mutch DM (2015) Metabolomics reveals metabolically healthy and unhealthy obese individuals differ in their response to a caloric challenge. PLoS One 10(8):e0134613 Belmonte F, Bisogno A, Troisi J et al (2017) Salivary levels of uric acid, insulin and HOMA: a promising field of study to non-invasively identify obese children at risk of metabolic syndrome and fatty liver. Dig Liver Dis 49:e247. https://doi.org/10.1016/j.dld.2017.09.017 Bervoets L, Massa G, Guedens W, Reekmans G, Noben J-P, Adriaensens P (2018) Identification of metabolic phenotypes in childhood obesity by (1)H NMR metabolomics of blood plasma. Fut Sci OA 4(6): FSO310. https://doi.org/10.4155/fsoa-2017-0146 Bluemel S, Williams B, Knight R, Schnabl B (2016) Precision medicine in alcoholic and nonalcoholic fatty liver disease via modulating the gut microbiota. Am J Phys Gastrointest Liver Phys 311(6):G1018– G1036 Boursier J, Mueller O, Barret M et al (2016) The severity of nonalcoholic fatty liver disease is associated with gut dysbiosis and shift in the metabolic function of the gut microbiota. Hepatology 63(3):764–775 Bussler S, Penke M, Flemming G et al (2017) Novel insights in the metabolic syndrome in childhood and adolescence. Horm Res Paediatr 88(3–4):181–193. https://doi.org/10.1159/000479510 Butte NF, Liu Y, Zakeri IF et al (2015) Global metabolomic profiling targeting childhood obesity in the Hispanic population. Am J Clin Nutr 102 (2):256–267. https://doi.org/10.3945/ajcn.115.111872 Buzzetti E, Pinzani M, Tsochatzis EA (2016) The multiple-hit pathogenesis of non-alcoholic fatty liver disease (NAFLD). Metabolism 65(8):1038–1048 Camacho JDH, Camacho MH (2017) Clinical update on metabolic syndrome. Rev Esp Nutri Hum Diet 21 (4):384–392 Centers for Disease Control and Prevention (CDC) (2019) CDC’s Childhood Obesity Research Demonstration (CORD) Project 3.0. https://www.cdc.gov/obesity/ strategies/healthcare/cord3.html. Accessed 26 Nov 2019 Chiappin S, Antonelli G, Gatti R, Elio F (2007) Saliva specimen: a new laboratory tool for diagnostic and basic investigation. Clin Chim Acta 383(1-2):30–40 Cho A-S, Jeon S-M, Kim M-J et al (2010) Chlorogenic acid exhibits anti-obesity property and improves lipid metabolism in high-fat diet-induced-obese mice. Food Chem Toxicol 48(3):937–943 Cho K, Moon JS, Kang J-H et al (2017a) Combined untargeted and targeted metabolomic profiling reveals urinary biomarkers for discriminating obese from normal-weight adolescents. Pediatr Obes 12 (2):93–101. https://doi.org/10.1111/ijpo.12114 Cho J, Hong H, Park S, Kim S, Kang H (2017b) Insulin resistance and its association with metabolic syndrome in Korean children. Biomed Res Int 2017:7

19

Salivary and Urinary Metabolome in Pediatric Obesity and Metabolic Syndrome

Cobbold JF, Anstee QM, Goldin RD et al (2009) Phenotyping murine models of non-alcoholic fatty liver disease through metabolic profiling of intact liver tissue. Clin Sci 116(5):403–413 Costa RF, Santos NS, Goldraich NP, Barski TF, de Andrade KS, Kruel LFM (2012) Metabolic syndrome in obese adolescents: a comparison of three different diagnostic criteria. J Pediatr 88(4):303–309. https:// doi.org/10.2223/JPED.2200 D’Adamo E, Santoro N, Caprio S (2009) Metabolic syndrome in pediatrics: old concepts revised, new concepts discussed. Endocrinol Metab Clin 38 (3):549–563 Dandona P, Aljada A, Chaudhuri A, Mohanty P, Garg R (2005) Metabolic syndrome: a comprehensive perspective based on interactions between obesity, diabetes, and inflammation. Circulation 111(11):1448–1454 Das VL, Purohit P, Sharma P, Das A (2014) Metabolic syndrome in pediatric age-a group requiring intensive review. J Obes Metabol Res 1(4):238 Desai GS, Mathews ST (2014) Saliva as a non-invasive diagnostic tool for inflammation and insulin-resistance. World J Diabetes 5(6):730–738. https://doi.org/10. 4239/wjd.v5.i6.730 Dietz WH, Robinson TN (2005) Overweight children and adolescents. N Engl J Med 352(20):2100–2109 Dinkova-Kostova AT, Wang XJ (2011) Induction of the Keap1/Nrf2/ARE pathway by oxidizable diphenols. Chem Biol Interact 192(1-2):101–106 Dodds MW, Johnson DA, Yeh C-K (2005) Health benefits of saliva: a review. J Dent 33(3):223–233 Dumas M-E, Barton RH, Toye A et al (2006) Metabolic profiling reveals a contribution of gut microbiota to fatty liver phenotype in insulin-resistant mice. Proc Natl Acad Sci 103(33):12511–12516 Dumas M-E, Kinross J, Nicholson JK (2014) Metabolic phenotyping and systems biology approaches to understanding metabolic syndrome and fatty liver disease. Gastroenterology 146(1):46–62 Eckel RH, Grundy SM, Zimmet PZ (2005) The metabolic syndrome. Lancet 365(9468):1415–1428 Elliott P, Posma JM, Chan Q et al (2015) Urinary metabolic signatures of human adiposity. Sci Transl Med 7 (285):285ra62 EPHORT Childhood Obesity Project (2016) RIVM DNI for PH and the E. https://ec.europa.eu/health/sites/ health/files/nutrition_physical_activity/docs/ev_ 20161123_co05_en.pdf. Accessed 26 Nov 2019 Esposito K, Ciotola M, Giugliano D (2007) Mediterranean diet and the metabolic syndrome. Mol Nutr Food Res 51(10):1268–1274 Ewaschuk JB, Dieleman LA (2006) Probiotics and prebiotics in chronic inflammatory bowel diseases. World J Gastroenterol 12(37):5941 Fabbrini E, Sullivan S, Klein S (2010) Obesity and nonalcoholic fatty liver disease: biochemical, metabolic, and clinical implications. Hepatology 51(2):679–689 Fekete Z, Korec R, Feketeova E et al (1993) Salivary and plasma insulin levels in man. Biochem Mol Biol Int 30 (4):623–629

261

Garrett JR, Ekström J, Anderson LC (1998) Glandular mechanisms of salivary secretion, vol 10. Karger Medical and Scientific Publishers, Basel Gawlik A, Shmoish M, Hartmann MF, Malecka-Tendera E, Wudy SA, Hochberg ZE (2016) Steroid metabolomic disease signature of nonsyndromic childhood obesity. J Clin Endocrinol Metab 101(11):4329– 4337. https://doi.org/10.1210/jc.2016-1754 Genuth S, Alberti KG, Bennett P, Buse J, Defronzo R, Kahn R, Kitzmiller J, Knowler WC, Lebovitz H, Lernmark A, Nathan D, Palmer J, Rizza R, Saudek C, Shaw J, Steffes M, Stern M, Tuomilehto J, Zimmet P (2003) Follow-up report on the diagnosis of diabetes mellitus diabetes. Diabetes Care 26:3160–3167 Goffredo M, Santoro N, Tricò D, Giannini C, D’Adamo E, Zhao H, Peng G, Yu X, Lam TT, Pierpont B, Caprio S, Herzog RI (2017) A branched-chain amino acid-related metabolic signature characterizes obese adolescents with non-alcoholic fatty liver disease. Nutrients 9 (7):642. https://doi.org/10.3390/nu9070642. PMID: 28640216; PMCID: PMC5537762 Goodson JM, Kantarci A, Hartman M-L et al (2014) Metabolic disease risk in children by salivary biomarker analysis. PLoS One 9(6):e98799. https://doi. org/10.1371/journal.pone.0098799 Guercio Nuzio S, Di Stasi M, Pierri L et al (2017) Multiple gut–liver axis abnormalities in children with obesity with and without hepatic involvement. Pediat Obes 12 (6):446–452 Hartman M-L, Goodson JM, Barake R et al (2016) Salivary biomarkers in pediatric metabolic disease research. Pediatr Endocrinol Rev 13(3):602–611 Hofman LF (2001) Human saliva as a diagnostic specimen. J Nutr 131(5):1621S–1625S Hosseinpour-Niazi S, Bakhshi B, Betru E, Mirmiran P, Darand M, Azizi F (2019) Prospective study of total and various types of vegetables and the risk of metabolic syndrome among children and adolescents. World J Diabetes 10(6):362 Jin R, Banton S, Tran VT et al (2016) Amino acid metabolism is altered in adolescents with nonalcoholic fatty liver disease—an untargeted, high resolution metabolomics study. J Pediatr 172:14–19 Kalhan SC, Guo L, Edmison J et al (2011) Plasma metabolomic profile in nonalcoholic fatty liver disease. Metabolism 60(3):404–413. https://doi.org/10.1016/j. metabol.2010.03.006 Kang M, Lee A, Yoo HJ et al (2017) Association between increased visceral fat area and alterations in plasma fatty acid profile in overweight subjects: a crosssectional study. Lipids Health Dis 16(1):248 Kelishadi R, Gouya MM, Ardalan G et al (2007) First reference curves of waist and hip circumferences in an Asian population of youths: CASPIAN study. J Trop Pediatr 53(3):158–164 Kumar S, Kelly AS (2017) Review of childhood obesity: from epidemiology, etiology, and comorbidities to clinical assessment and treatment. Mayo Clin Proc 92:251–265 Kushner RF (2014) Weight loss strategies for treatment of obesity. Prog Cardiovasc Dis 56(4):465–472

262 Lakshman R, Elks CE, Ong KK (2012) Childhood obesity. Circulation 126(14):1770–1779 Le Chatelier E, Nielsen T, Qin J et al (2013) Richness of human gut microbiome correlates with metabolic markers. Nature 500(7464):541 Leal-Witt MJ, Llobet M, Samino S, Castellano P, Cuadras D, Jimenez-Chillaron JC, Yanes O, Ramon-Krauel M, Lerin C (2018) Lifestyle intervention decreases urine trimethylamine N-Oxide levels in prepubertal children with obesity. Obesity 26:1603–1610. https://doi.org/ 10.1002/oby.22271 Ma Y, Gao M, Liu D (2015) Chlorogenic acid improves high fat diet-induced hepatic steatosis and insulin resistance in mice. Pharm Res 32(4):1200–1209 Magge SN, Goodman E, Armstrong SC (2017) The metabolic syndrome in children and adolescents: shifting the focus to cardiometabolic risk factor clustering. Pediatrics 140:e20171603. https://doi.org/10.1542/ peds.2017-1603 Martos-Moreno GA, Sackmann-Sala L, Barrios V et al (2014) Proteomic analysis allows for early detection of potential markers of metabolic impairment in very young obese children. Int J Pediatr Endocrinol 2014 (1):9. https://doi.org/10.1186/1687-9856-2014-9 Miccheli A, Capuani G, Marini F et al (2015) Urinary (1) H-NMR-based metabolic profiling of children with NAFLD undergoing VSL#3 treatment. Int J Obes 39 (7):1118–1125. https://doi.org/10.1038/ijo.2015.40 Morales Camacho WJ, Molina Díaz JM, Plata Ortiz S, Plata Ortiz JE, Morales Camacho MA, Calderón BP (2019) Childhood obesity: aetiology, comorbidities, and treatment. Diabetes Metab Res Rev 35:e3203 Mussavira S, Dharmalingam M, Omana SB (2015) Salivary glucose and antioxidant defense markers in type II diabetes mellitus. Turk J Med Sci 45(1):141–147 Napoli Study (2019) University of Salerno. November. https://napolistudy.org. Nejatinamini S, Ataie-Jafari A, Qorbani M et al (2015) Association between serum uric acid level and metabolic syndrome components. J Diab Metab Disord 14:70. https://doi.org/10.1186/s40200-015-0200-z Newgard CB, An J, Bain JR et al (2009) A branched-chain amino acid-related metabolic signature that differentiates obese and lean humans and contributes to insulin resistance. Cell Metab 9(4):311–326 Nunes S, Alessandro L, Mussavira S, Sukumaran BO (2015) Clinical and diagnostic utility of saliva as a non-invasive diagnostic fluid: a systematic review. Biochem Med Biochem Med 25(2):177–192 Ogobuiro I, Tuma F (2019) Physiology, renal. In: StatPearls [Internet]. StatPearls Publishing. Pandey KB, Rizvi SI (2009) Plant polyphenols as dietary antioxidants in human health and disease. Oxidative Med Cell Longev 2(5):270–278 Pastore A, Alisi A, di Giovamberardino G et al (2014) Plasma levels of homocysteine and cysteine increased in pediatric NAFLD and strongly correlated with severity of liver damage. Int J Mol Sci 15 (11):21202–21214

J. Troisi et al. Patti AM, Al-Rasadi K, Katsiki N et al (2015) Effect of a natural supplement containing curcuma longa, guggul, and chlorogenic acid in patients with metabolic syndrome. Angiology 66(9):856–861 Pfaffe T, Cooper-White J, Beyerlein P, Kostner K, Punyadeera C (2011) Diagnostic potential of saliva: current state and future applications. Clin Chem 57 (5):675–687 Pierri L, Troisi J, Bisogno A et al (2018) A metabolomic salivary signature of pediatric obesity related liver disease. J Pediatr Gastroenterol Nutr 66:642–643 Pitsavos C, Panagiotakos DB, Tzima N et al (2007) Diet, exercise, and C-reactive protein levels in people with abdominal obesity: the ATTICA epidemiological study. Angiology 58(2):225–233 Rosenbaum M (2018) Special considerations relevant to pediatric obesity. In: Endotext [Internet]. MDText. com, Inc. Rutigliano I, Vinci R, De Filippo G et al (2017) Metabolic syndrome, hepatic steatosis, and cardiovascular risk in children. Nutrition 36:1–7. https://doi.org/10.1016/j. nut.2016.10.017 Saint-Georges-Chaumet Y, Edeas M (2015) Microbiota– mitochondria inter-talk: consequence for microbiota– host interaction. FEMS Pathog Dis 74(1):ftv096 Santana-Gálvez J, Cisneros-Zevallos L, Jacobo-Velázquez DA (2017) Chlorogenic acid: recent advances on its dual role as a food additive and a nutraceutical against metabolic syndrome. Molecules 22(3):358 Sanyal AJ, Campbell-Sargent C, Mirshahi F et al (2001) Nonalcoholic steatohepatitis: association of insulin resistance and mitochondrial abnormalities. Gastroenterology 120(5):1183–1192 Soga T, Sugimoto M, Honma M et al (2011) Serum metabolomics reveals γ-glutamyl dipeptides as biomarkers for discrimination among different forms of liver disease. J Hepatol 55(4):896–905. https://doi. org/10.1016/j.jhep.2011.01.031 Spruijt-Metz D (2011) Etiology, treatment, and prevention of obesity in childhood and adolescence: a decade in review. J Resear Adoles 21(1):129–152 Stohs SJ, Preuss HG, Shara M (2011) A review of the receptor-binding properties of p-synephrine as related to its pharmacological effects. Oxidative Med Cell Longev 2011:482973 STOP (2019) Science and Technology in childhood Obesity Policy. http://www.stopchildobesity.eu/. Accessed 26 Nov 2019 Takato T, Iwata K, Murakami C, Wada Y, Sakane F (2017) Chronic administration of myristic acid improves hyperglycaemia in the Nagoya–Shibata– Yasuda mouse model of congenital type 2 diabetes. Diabetologia 60(10):2076–2083 Tenore GC, Troisi J, Di Fiore R, Manfra M, Novellino E (2011) Nutraceutical value and toxicological profile of selected red wines from Morocco. Food Chem 129 (3):792–798. https://doi.org/10.1016/j.foodchem. 2011.05.022

19

Salivary and Urinary Metabolome in Pediatric Obesity and Metabolic Syndrome

Tenore GC, Giorgio C, Stiuso P, Ritieni A, Giannetti D, Novellino E (2014) Effects of annurca apple polyphenols on lipid metabolism in HepG2 cell lines: a source of nutraceuticals potentially indicated for the metabolic syndrome. Food Res Int 63:252–257 Tiniakos DG, Vos MB, Brunt EM (2010) Nonalcoholic fatty liver disease: pathology and pathogenesis. An Rev Pathol Mech Dis 5:145–171 Topp H, Fusch G, Schöch G, Fusch C (2008) Noninvasive markers of oxidative DNA stress, RNA degradation and protein degradation are differentially correlated with resting metabolic rate and energy intake in children and adolescents. Pediatr Res 64(3):246 Tresaco B, Bueno G, Pineda I, Moreno LA, Garagorri JM, Bueno M (2005) Homeostatic model assessment (HOMA) index cut-off values to identify the metabolic syndrome in children. J Physiol Biochem 61 (2):381–388 Troisi J, Pierri L, Landolfi A et al (2017) Urinary metabolomics in pediatric obesity and NAFLD identifies metabolic pathways/metabolites related to dietary habits and gut-liver axis perturbations. Nutrients 9(5):E485. https://doi.org/10.3390/ nu9050485 Troisi J, Belmonte F, Bisogno A et al (2018) Salivary markers of hepato-metabolic comorbidities in pediatric obesity. Dig Liver Dis 51:P516–P523. https://doi.org/ 10.1016/j.dld.2018.11.009 Troisi J, Belmonte F, Bisogno A et al (2019) Metabolomic salivary signature of pediatric obesity related liver disease and metabolic syndrome. Nutrients 11(2):274. https://doi.org/10.3390/nu11020274 Turnbaugh PJ, Ley RE, Mahowald MA, Magrini V, Mardis ER, Gordon JI (2006) An obesity-associated gut microbiome with increased capacity for energy harvest. Nature 444(7122):1027–1031. https://doi.org/ 10.1038/nature05414 Urakami T, Morimoto S, Nitadori Y, Harada K, Owada M, Kitagawa T (2007) Urine glucose screening program at schools in Japan to detect children with diabetes and its

263

outcome-incidence and clinical characteristics of childhood type 2 diabetes in Japan. Pediat Resear 61(2):141 Vajro P, Paolella G, Fasano A (2013a) Microbiota and gut-liver axis: their influences on obesity and obesityrelated liver disease. J Pediatr Gastroenterol Nutr 56 (5):461–468. https://doi.org/10.1097/MPG. 0b013e318284abb5 Vajro P, Paolella G, Fasano A (2013b) Microbiota and gut-liver axis: a mini-review on their influences on obesity and obesity related liver disease. J Pediatr Gastroenterol Nutr 56(5):461 Wahba IM, Mak RH (2007) Obesity and obesity-initiated metabolic syndrome: mechanistic links to chronic kidney disease. Clin J Am Soc Nephrol 2(3):550–562 WHO (2016) Ending childhood obesity: report of the Commission on Ending Childhood Obesity (ECHO). http://apps.who.int/iris/bitstream/10665/204176/1/ 9789241510066_eng.pdf?ua¼1. Wiklund PK, Pekkala S, Autio R et al (2014) Serum metabolic profiles in overweight and obese women with and without metabolic syndrome. Diabetol Metab Syndr 6(1):40. https://doi.org/10.1186/17585996-6-40 Wisse BE (2004) The inflammatory syndrome: the role of adipose tissue cytokines in metabolic disorders linked to obesity. J Am Soc Nephrol 15(11):2792–2800 Wittcopp C, Conroy R (2016) Metabolic syndrome in children and adolescents. Pediatr Rev 37(5):193 Wurtz P, Makinen V-P, Soininen P et al (2012) Metabolic signatures of insulin resistance in 7,098 young adults. Diabetes 61(6):1372–1380. https://doi.org/10.2337/ db11-1355 Zafar U, Khaliq S, Ahmad HU, Manzoor S, Lone KP (2018) Metabolic syndrome: an update on diagnostic criteria, pathogenesis, and genetic links. Hormones 17 (3):299–313 Zimmet P, Alberti KGM, Kaufman F et al (2007) The metabolic syndrome in children and adolescents—an IDF consensus report. Pediatr Diabetes 8(5):299–306. https://doi.org/10.1111/j.1399-5448.2007.00271.x

‘State-of-the-Art’ Metabolomics Investigations of Type 2 Diabetes

20

Benita Percival, Justine Leenders, and Martin Grootveld

Contents The Role of Metabolomics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 The Normal and Pathological Metabolome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 Targeted vs. Untargeted Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 Biomarkers of Type 2 Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Serum and Plasma Biomarkers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Saliva . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Urine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

267 267 272 273

Disturbed Metabolic Pathways Involved in T2D Pathogenicity . . . . . . . . . . . . . . . . . . . 275 Personal Experience: Retrospective Network Pathway Analysis of Published Data . . 275 Prognostic Fingerprints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276 Short vs. Long-term Glycemic Homeostasis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 Kidney Dysfunction and Ketosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 Potential Bedside/’Point-of-Care’ Metabolomics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 Future Developments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bedside Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Metabolomic Panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Portable Oral Prosthesis and Breath Volatolomic Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . Artificial Pancreas and Wearable Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

279 279 280 280 280

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280

Abstract

Metabolomics represents the global investigation of complex biomolecular patterns in living systems, i.e. in organs, cells, tissues or biofluids, and the understanding of how clinically significant deviations from such patterns B. Percival · J. Leenders · M. Grootveld (*) Leicester School of Pharmacy, De Montfort University, Leicester, UK e-mail: [email protected]

may facilitate our knowledge of the pathogenesis of human diseases. This now widely expanded research area has been extensively applied to the prognostic monitoring of type 2 diabetes (T2D), particularly in human biofluids. The achievements of T2D metabolomics investigations include the identification of key biomarkers in human biofluid samples, which may also be employed for determining individuals at risk of this condition. T2D biomarkers arise from disturbed

# Springer Nature Switzerland AG 2020 J. Faintuch and S. Faintuch (eds.), Obesity and Diabetes, https://doi.org/10.1007/978-3-030-53370-0_20

265

266

metabolic pathways, which include those distinct from glycolysis and lipid metabolism. Additionally, prognostic fingerprints and biomarkers of insulin resistance have been explored using metabolomics analysis, and these strategies have been critically evaluated for their possible future ‘point-of-care’ uses in clinical settings. The potential advancement for such ‘bedside’ metabolomics tests and the future direction of metabolomics in T2D is discussed in detail.

Keywords

Diabetes biomarkers · Plasma metabolome · Saliva metabolome · Urine metabolome · Diabetes metabolic pathways · Diabetes prognostic fingerprints · Bedside metabolome

The Role of Metabolomics Although the metabolome was first explored centuries ago, through organoleptic tasting analysis and smell of urine as a means of diagnosing diseases, applications of bioanalytical techniques to simultaneously analyse more than one class of biomolecules in urine were first performed by Pauling et al. (1971), and the human metabolome was first described by Oliver et al. (1998). Over the last 20 years, the metabolome itself and means for the utilisation of multianalyte bioanalytical techniques that can be applied to it, have been further defined by others such as Nicholson and Lindon (2008), and many developments have been explored in the literature, with a progressive history of techniques employed for these studies, along with their establishment as key investigatory tools (documented by Kell and Oliver (2016)).

The Normal and Pathological Metabolome The study of the metabolome allows for the monitoring of metabolic processes within a system by

B. Percival et al.

assessment of low-molecular-mass metabolites within biofluids, tissues, cells or other biosamples. Indeed, the metabolome can be affected by many biological processes. These can either be through external stimuli such as medical intervention, i.e. medication, diet or an exercise regimen, or through internal stimuli. An internal stimulus can be introduced by the modification of gene expression using techniques such as cell transfection, both in vivo and in vitro. Moreover, metabolomics techniques assess these changes by providing a ‘snapshot’ of the status of biological processes occurring at a specific point in time. This responsive information can provide a high level of detail regarding cellular metabolic processes, may facilitate phenotypic evaluations, and therefore yields an overall ‘picture’ or ‘fingerprint’ of a disease’s chemopathological status. Even more valuably, metabolomics is able to probe changing disease status, e.g. the effects of metformin therapy or the regression of inflammatory conditions, in type 2 diabetes (T2D), as can the influence of dietary or physical exercise interventions. Hence, these strategies may be successfully employed to monitor disease severity and progression, information which further increases our understanding of the aetiology, manifestation and progression of particular conditions (German et al. 2005). A combination of metabolomic strategies has been previously applied to pre-diabetes (Zeng et al. 2017), type 1 diabetes (Haukka et al. (2018)), T2D and gestational diabetes (Bentley-Lewis et al. 2015).

Targeted vs. Untargeted Approach Leading metabolomics techniques are largely untargeted ones and aim to simultaneously detect all possible metabolites present in biological samples. This multicomponent quantitative bioanalytical approach differs from targeted metabolomics investigations, which focus on the analysis of only limited numbers or classes of metabolites that are linked via specific biochemical pathways. Typical techniques include nuclear magnetic resonance (NMR) and liquid chromatography-mass spectrometric (LC-MS)

20

‘State-of-the-Art’ Metabolomics Investigations of Type 2 Diabetes

analyses, which are readily applicable to a wide range of biosamples (Zhang et al. 2012). Briefly, high-resolution NMR analysis is able to detect and quantify metabolites in a high-throughput, simultaneous, non-destructive manner requiring minimal sample preparation. LC-MS strategies, however, can target specific metabolites more sensitively than NMR, whilst lacking the specificity of the latter for absolute metabolite determinations (Sandlers 2017). Therefore, a combination of both LC-MS and NMR methodologies is important for a global understanding of metabolic effects involved in disease processes, and can be essential for thorough determinations of the metabolic status of biofluids and tissue biopsies. Alternative analytical techniques include Fourier transform infrared (FTIR) and Raman spectroscopies (Lindon et al. 2011).

Biomarkers of Type 2 Diabetes One of the first diagnoses of diabetes was performed in fifth/sixth century BC using a urine sample, and this arose from a physician, Sushruta, acknowledging frequent urination in subjects with this condition, and ants being attracted to the urine (Sharma and Chandola 2011). This knowledge is still applied today in rural areas in different parts of the world, for example in Vietnam (Mull, Nguyen and Mull 2001). Diabetes mellitus became the designated terminology for these patients, which is Latin for abundant flux (of urine) and ‘honeyed’ or ‘sweet,’ respectively. Currently, common biomarkers that are detected in clinical settings include glucose and ketone bodies in urine and plasma, as well as glycosylated haemoglobin A1c (HbA1c) in whole blood. HbA1c reflects the success of therapeutic control by T2D patients self-administering injectable insulin or oral hypoglycaemic agents such as metformin, throughout a 6–8 week period. However, there are many more markers that can provide further information regarding the status of T2D, e.g. ketone bodies and branched-

267

chain amino acids (BCAAs). These alternative biomarkers can provide valuable information regarding the early detection of T2D, i.e. prior to its full onset, a development which can give rise to improved outcomes for patients. To date, a combination of biofluids and tissues has been investigated in animals and humans, including blood serum (Drogan et al. 2015; Floegel et al. 2013), blood plasma, urine and saliva. Table 20.1 provides insight into biomarkers that have been suggested to be clinically significant, regarding T2D diagnosis in serum or plasma, urine and saliva.

Serum and Plasma Biomarkers One of the largest metabolomics studies exploring diabetes was performed with samples collected during the European Prospective Investigation into Cancer and Nutrition (EPIC) (Floegel et al. 2013; Drogan et al. 2015). Floegel et al. (2013) used flow injection analysis mass spectrometry/mass spectrometry (FIA-MS/MS) to determine serum metabolites from control (n ¼ 1482) and T2D (n ¼ 800) participants. The global metabolome of this cohort was monitored over a mean 7-year period to observe the increased or decreased risk of T2D form the status of biomolecular analytes. Upregulations in hexose, phenylalanine and diacylphosphatidylcholines (C32:1, C36:1, C38:3 and C40:5), along with downregulations in glycine, sphingomyelin (C16:1), acyl-alkyl-phosphatidylcholines (C34:3, C40:6, C42:5, C44:4 and C44:5) and lysophosphatidylcholine (C18:2) were observed in T2D patients. Drogan et al. (2015) observed 300 individuals who provided serum samples at the beginning of a trial, and also after a median of 6 years, in an untargeted LC-MS investigation. Significant metabolite markers included lysophosphatidylcholine (demethyl 16:0) and phosphatidylcholine (oleoyl-20:0/ oleoyl-20:0), which were all downregulated in T2D. As expected, hexose sugars such as glucose were elevated in T2D plasma. In another protocol, glyoxylate was observed to be upregulated

268

B. Percival et al.

Table 20.1 A summary of metabolite markers that are disturbed in Type 2 Diabetes (T2D) whole blood, serum and plasma, urine and saliva in humans Potential Marker Biofluid Lipids, fatty acids Diacyl-phosphatidylcholines C32:1, C36:1, C38:3 Serum and C40:5 Lysophosphatidylcholine C18:2 Serum Lysophosphatidylcholine (dm16:0) and Serum phosphatidylcholine (O-20:0/O-20:0) Stearate Serum Palmitate Serum Glycerophospholipids Serum Sphingomyelins Serum Myristic Acid Serum 15-Methyl palmitate Plasma 10-Heptadecanoate Plasma Adrenate (22:4 (n-6)) Plasma Arachidonate (20:4 (n-6)) Plasma Myristate (14:0) Plasma Myristoleate (14:1 (n-5)) Plasma Palmitoleate (16:1 (n-5)) Plasma Pentanedionate (15:0) Plasma 5-Dodecanoate (12:1 (n¼7)) Plasma Heptanoate (7:0) Plasma Pelargonate (9:0) Plasma Palmitoyl Sphingomyelin Plasma Cholesterol Plasma Low-molecular-mass Molecules (e.g. BCAAs and TCA cycle) 1-Methylhistidine Plasma Urine 2-Deoxyglucose Plasma 2-Hydroxybutyrate Plasma Serum Urine Saliva

Increased/ decreased

Technique

References

#

MS

Floegel et al. (2013)

" #

MS MS

Floegel et al. (2013) Drogan et al. (2015)

" " # # " # # " " # # # # # # # # #

MS MS MS MS MS MS MS MS MS MS MS MS MS MS MS MS MS MS

Xu et al. (2013) Xu et al. (2013) Xu et al. (2013) Xu et al. (2013) Xu et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013) Menni et al. (2013)

MS MS MS MS MS MS MS MS MS 1 H NMR MS

Yousri et al. (2015)

MS MS MS MS MS MS MS MS MS 1 H NMR 1 H NMR MS

3-D-Hydroxybutyrate

Plasma Urine

# # " " " " " # " "

3-Hydroxyproline 3-Methoxytyrosine

Urine Plasma Urine Plasma Plasma Plasma Urine Plasma Urine Urine Urine

" # # " " " " " # " "

3-Methyl-2-oxobutyrate 3-Methyl-3-oxovalerate 4-Hydroxyphenylpyruvate 4-Methyl-2-oxopentanoate 5-Oxoproline Acetate Acetoacetate

Suhre et al. (2010) Yousri et al. (2015) Menni et al. (2013) Xu et al. (2013) Yousri et al. (2015) Barnes et al. (2014) Yousri et al. (2015) Suhre et al. (2010) Salek et al. (2007) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) Menni et al. (2013) Menni et al. (2013) Yousri et al. (2015) Yousri et al. (2015) Menni et al. (2013) Yousri et al. (2015) Salek et al. (2007) Salek et al. (2007) Yousri et al. (2015) (continued)

20

‘State-of-the-Art’ Metabolomics Investigations of Type 2 Diabetes

269

Table 20.1 (continued) Potential Marker Adipate Alanine

Biofluid Urine Serum Urine

Increased/ decreased # # " "

Allantoin Aminohippurate Betaine Carnitine Citrate

Urine Urine Urine Serum Serum Urine Plasma

# # " # # " #

Creatine Creatinine

Serum Serum Urine

# # #

Cysteine Dimethylamine Dimethylglycine

Urine Urine Urine

" " "

Ethanolamine Fumarate Glutamate

Urine Urine Serum Urine

# # # #

Glycerol

Serum

"

MS H NMR 1 H NMR MS 1 H-NMR 1 H-NMR

Glycine Glutamine

Serum Serum Serum

# # " " # #

MS H NMR MS MS MS 1 H NMR

Citrulline

Glyoxylate Heptanoate Hippurate

Plasma Urine

Technique MS 1 H NMR MS MS 1 H NMR 1 H NMR 1 H NMR MS 1 H NMR 1 H NMR 1 H NMR MS 1

H NMR H NMR 1 H NMR/ MS MS 1 H NMR 1 H NMR MS 1

1

1

Homocitrulline Homocysteine Homovanillate Isobutyrylcarnitine Isoleucine

Urine Urine Urine Urine Serum Plasma Urine

# # # # # " " " "

MS MS MS MS 1 H NMR MS 1 H NMR MS MS

Kynurenate

Plasma Urine

# #

MS MS

References Yousri et al. (2015) Coco et al. (2019) Xu et al. (2013) Yousri et al. (2015) Urpi-Sarda et al. (2019) Salek et al. (2007) Salek et al. (2007) Svingen et al. (2016) Coco et al. (2019) Coco et al. (2019) Urpi-Sarda et al. (2019) Yousri et al. (2015) Menni et al. (2013) Coco et al. (2019) Coco et al. (2019) Salek et al. (2007) Yousri et al. (2015) Yousri et al. (2015) Salek et al. (2007) Salek et al. (2007) Urpi-Sarda et al. (2019) Urpi-Sarda et al. (2019) Yousri et al. (2015) Salek et al. (2007) Coco et al. (2019) Yousri et al. (2015) Urpi-Sarda et al. (2019) Aloha-Ollie et al. (2019) Floegel et al. (2013) Coco et al. (2019) Xu et al. (2013) Nikiforova et al. (2014) Yousri et al. (2015) Salek et al. (2007) Urpi-Sarda et al. (2019) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) Coco et al. (2019) Xu et al. (2013) Aloha-Ollie et al. (2019) Menni et al. (2013) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) (continued)

270

B. Percival et al.

Table 20.1 (continued) Increased/ decreased # " " " "

Potential Marker Leucine

Biofluid Serum Plasma Urine

Lysine L-Octanoylcarnitine Malate

Serum Plasma Plasma

# # "

H NMR MS MS

Methionine Myo-inositol N-acetylaspartate N-acetyl groups (including glycoproteins) N-acetylglycine N-acetyl-β-alanine N-butyrate N-methylnicotinate N-methylnicotinamide Ornithine

Serum Urine Urine Urine

# # " #

1

H NMR MS 1 H NMR 1 H NMR

Plasma Urine Urine Urine Urine Plasma Urine Serum Plasma Urine

# " " # " # " # " " " "

MS MS 1 H NMR 1 H NMR 1 H NMR MS MS 1 H NMR MS MS 1 H NMR MS MS 1 H NMR

Urine Serum Plasma Urine Serum Plasma Urine Saliva Urine Urine Urine Serum Plasma Serum Plasma

" " " " # # # # " # # # " # " " # " " " "

MS MS MS MS MS MS MS MS MS 1 H NMR MS 1 H NMR MS 1 H NMR MS MS MS MS MS MS MS

Phenylalanine

Pipecolate Proline

Pyroglutamine

Sarcosine Succinate Trans-urocanate Tyrosine Urea Valine

Vanillylmandelate α-Ketobutyrate β-Hydroxypyruvate

Urine Plasma Urine Plasma Urine

Technique H NMR MS 1 H NMR MS MS 1

1

References Coco et al. (2019) Xu et al. (2013) Aloha-Ollie et al. (2019) Menni et al. (2013) Yousri et al. (2015) Coco et al. (2019) Menni et al. (2013) Yousri et al. (2015) Menni et al. (2013) Coco et al. (2019) Yousri et al. (2015) Salek et al. (2007) Salek et al. (2007) Menni et al. (2013) Yousri et al. (2015) Salek et al. (2007) Salek et al. (2007) Salek et al. (2007) Yousri et al. (2015) Yousri et al. (2015) Coco et al. (2019) Floegel et al. (2013) Xu et al. (2013) Aloha-Ollie et al. (2019) Suhre et al. (2010) Yousri et al. (2015) Urpi-Sarda et al. (2019) Yousri et al. (2015) Xu et al. (2013) Menni et al. (2013) Yousri et al. (2015) Xu et al. (2013) Yousri et al. (2015) Yousri et al. (2015) Barnes et al. (2014) Svingen et al. (2016) Salek et al. (2007) Yousri et al. (2015) Coco et al. (2019) Menni et al. (2013) Coco et al. (2019) Xu et al. (2013) Menni et al. (2013) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) (continued)

20

‘State-of-the-Art’ Metabolomics Investigations of Type 2 Diabetes

271

Table 20.1 (continued) Biofluid

Increased/ decreased

Technique

References

Plasma Plasma Saliva

" # #

MS MS MS

2-Methylcitrate 3-Hydroxyisobutyrate Arabinose Arabitol Fructose

Urine Plasma Plasma Urine Plasma

# # " # "

MS MS MS MS MS

Gluconate Glucose

Plasma Plasma Serum Urine Saliva

" " " " "

MS MS 1 H NMR MS MS

Lactate

Plasma Serum Urine

" # "

1

Mannose

Plasma Urine

" "

MS MS

Pyruvate Ribose Threonate Xylonate

Plasma Urine Urine Urine

" # # #

MS MS MS MS

Yousri et al. (2015) Yousri et al. (2015) Suhre et al. (2010) Barnes et al. (2014) Menni et al. (2013) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) Menni et al. (2013) Yousri et al. (2015) Yousri et al. (2015) Menni et al. (2013) Yousri et al. (2015) Yousri et al. (2015) Barnes et al. (2014) Suhre et al. (2010) Menni et al. (2013) Coco et al. (2019) Yousri et al. (2015) Barnes et al. (2014) Yousri et al. (2015) Menni et al. (2013) Coco et al. (2019) Yousri et al. (2015) Yousri et al. (2015) Suhre et al. (2010) Menni et al. (2013) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015) Yousri et al. (2015)

Potential Marker Carbohydrates and Derivatives 1,3-Dihydroxyacetone 1,5-Anhydroglucitol

MS H NMR MS

The arrows represent upregulations or downregulations in T2D relative to control samples Abbreviations: NMR, Nuclear Magnetic Resonance; MS, Mass Spectrometry

using GC-MS, and recommended it as early marker for T2D (Nikiforova et al. 2014).

Amino Acids and Phospholipids 1 H NMR analysis has also been applied to serum metabolites in T2D patients (n ¼ 26) and controls (n ¼ 7) (Coco et al. 2019). Serum alanine, glutamine, glutamate, leucine, lysine, methionine, tyrosine and phenylalanine were all downregulated in T2D participants (Coco et al. 2019). Interestingly, these biomarker findings

contrast with those established by other researchers (Table 20.1). Similar findings to Drogan et al. (2015) were observed in a LC-MS and GC-MS metabolomics investigation, and significantly elevated fructose, α-hydroxybutyrate, alanine, proline, phenylalanine, glutamine, leucine, isoleucine, valine, mysterate, palmitate and stearate levels were observed, together with diminished pyroglutamate, glycerophospholipids and sphingomyelins, in the serum of groups of

272

patients with either impaired fasting glucose levels or T2D (Xu et al. 2013). Menni et al. (2013) observed 447 metabolites from fasted plasma samples from females with T2D (n ¼ 115), individuals with impaired fasting glucose (n ¼ 192) and controls (n ¼ 1897) using ultraperformance liquid chromatography–mass spectrometry (UPLC-MS). Of 447 metabolites analysed, 42 were observed to be significantly different on comparison of these two groups (Menni et al. 2013), as noted in Table 20.1.

Prognostic Metabolites Aloha-Ollie et al. (2019) quantified over 229 metabolites, including amino acids, fatty acids, glycolysis-related metabolites and lipoproteins using 1H NMR analysis in 11,896 individuals, including T2D (n ¼ 293) and controls (n ¼ 11,603) from four Finnish cohorts. The biomarkers that were identified as the strongest indication for this condition included elevated aromatic amino acids, vLDL particles and triacylglycerols (TAGs). Biomarkers shown to be significant for individuals at risk of T2D included elevated glycerol and mono-unsaturated fatty acids and ‘acute-phase’ glycoproteins. Proposed biomarkers associated with a lower risk of developing T2D included glutamine, linoleate and HDL-triacylglycerols. Liu et al. (2017) used a combination of liquid chromatography-mass spectrometry (LC-MS), and NMR combined with a least absolute shrinkage and selection operator regression approach, to identify biomarkers that were present in T2D blood samples (n ¼ 349), compared to age-matched controls (n ¼ 3998). In the 14 year follow-up study, similar findings to those of Aloha-Ollie et al. (2019) were found. There were clear disturbances in amino acid metabolism, including pathways featuring isoleucine and tyrosine. Further metabolic differences included those in triacylglycerols (TAGs), lactate, glycerol, pyruvate and vLDL-TAGs. Some of the markers for insulin resistance include glucose, mannose, α-hydroxybutyrate (α-HB) and α-tocopherol, in addition to selected

B. Percival et al.

amino acids and 1-linoleoyl glycerophosphocholine (Peddinti et al. 2017). Elevated α-hydroxybutyrate (HB) is also a marker of glucose intolerance (Peddinti et al. 2017). Branchedchain amino acids (BCAAs) are particularly important since they have been demonstrated to predict T2D 12 years prior to its onset (Wang et al. 2011).

Saliva Saliva is often proposed as an ideal biofluid for non-invasive analysis of diseases in view of its easy sample collection and its ability to reflect the contents of blood (Yousri et al. 2015; Barnes et al. 2014). Glucose is one of the metabolites that is elevated in the saliva of T2D patients (Gupta et al. 2014; Kadashetti et al. 2015). To determine salivary metabolites, Gupta et al. (2014) collected postprandial, unstimulated whole saliva. Participants were requested to rinse with water thoroughly and not to swallow for a period of 5 min before spitting into a sterile container. Kadashetti et al. (2015) collected fasting salivary samples, also requesting participants to wash their mouths with water. Yousri et al. (2015) collected salivary samples ~2 hr. post-prandially, and critically evaluated the limitations of non-fasted samples in their investigation.

Acetone and Lactate Acetone has been determined as significantly increased in patients with diabetes in ketoacidosis (Fuji et al. 2014). Other metabolic changes that have been observed include the ratio of D- to L-lactate levels in dried salivary spots from controls (n ¼ 68), pre-diabetic (n ¼ 30) and T2D (n ¼ 5) patients, in which T2D participants had a significantly higher ratio (Numako et al. 2016). The levels of D- and L-lactate were targeted in view of an upregulation of its methylglyoxal precursor, which arises from diabetic complications (Numako et al. 2016). The Dto L-lactate ratio showed good agreement with Hba1c values of blood in patients with diabetes;

20

‘State-of-the-Art’ Metabolomics Investigations of Type 2 Diabetes

however, the correlation of Hba1c values with Dto L-lactate ratio was poor in pre-diabetic samples (Numako et al. 2016). As in the study by Yousri et al. (2015), salivary samples were collected ~2 h. post-prandially (Numako et al. 2016).

Other Biomolecules Additional disturbances have been observed in glycated proteins, electrolytes, albumin and enzymes (e.g. amylase (Abd-Elraheem et al. 2017), lysozyme and peroxidase) (Negrato and Tarzia 2010), however, and not using NMR and MS metabolomics-based approaches described here. Using an MS strategy, Yousri et al. (2015) found three significant metabolites in diabetic saliva including downregulations in pyroglutamine and 1,5-anhydroglucitol (1,5-AG). Some disturbances in unidentified metabolites in saliva were also documented as part of this investigation (Yousri et al. 2015). Significant salivary metabolites might present as a viable option for point-of-care sampling in a clinical setting. Oral Diseases and Other Confounding Factors Dental hygiene status can, of course, markedly influence salivary results, and periodontal diseases show some significant differences in salivary profiles when compared to healthy controls (Aimetti, et al. 2012). Epidemiological studies have shown that periodontitis was observed to be 3 times higher in diabetes patients, specifically poorly controlled individuals (Mealey and Ocampo 2000). Nevertheless, an investigation showed that controls with/without periodontitis and diabetic patients with/without periodontitis all have unique metabolomic profiles when assessed using GC-MS/LC-MS (Barnes et al. 2014). Moreover, Barnes et al. (2014) detected significantly different levels of 1,5-AG, glucose and α-hydroxybutyrate in the salivary profiles of T2D participants from those of healthy controls. These levels had larger fold-changes than those observed in the plasma profiles. Significant alterations were observed in saliva samples with diabetes and gingivitis as a co-morbidity when compared to diabetes patients without gingivitis,

273

and predominantly increased salivary levels of fatty acids and sphingomyelins, along with changes in purine degradation and antioxidant status (Barnes et al. 2014).

Sample Contamination Food debris, nasal mucus and traces of blood severely impact metabolomics results, if samples are not carefully collected. The overall outlook for salivary metabolomics does, however, show much potential, as patients are much more comfortable providing this sample type of sample than others involving more invasive collection regimens.

Urine Urine is also very easy to collect and provides high sample volumes. Moreover, this biofluid contains many hundreds of metabolites that are readily detectable. LC-MS investigations have been performed on urinary samples of T2D (Svingen et al. 2016), with downregulation of betaine, dimethylglycine and sarcosine characteristic of T2D samples. 1H NMR investigations also found T2D downregulations of betaine and dimethylglycine, as well as of acetoacetate, acetate, n-butyrate, 3-hydroxybutyrate, dimethylamine, N-methylnicotinate (NMN) amide and N-acetyl aspartate (NAA), along with downregulated creatinine, N-acetyl functions, nicotinamide mononucleotide acid (NMN), aminohippurate, phenylacetylglycine (PAG), hippurate, allantoin, fumarate and succinate. Twelve control participants provided 7 samples each (total n ¼ 84 samples) and 30 T2D participants provided 1–3 samples (total n ¼ 50 samples). Figures 20.1 and 20.2 demonstrate how the metabolite information can be simultaneously obtained, in a typical diabetic urine sample, using NMR analysis with both 1D and 2D profiling approaches. In a different investigation, urinary betaine concentrations have also been demonstrated to be lower in participants with T2D; this metabolite was determined by LC-MS/MS analysis (Svingen et al. 2016), and this observation is consistent

274

B. Percival et al. [22][21]

a

[14]

[20]

[11]

[31]

[12]

[23] [24]

[10] [8]

[29] [P] [28] [30] [26] [25] [27]

[34]

[19]

[4] [7][6] [2] [1] [5]

[17]

[33] [32]

2.3 2.2

2.1 2.0

[3]

[15] [13]

[18] [16]

3.0 2.9 2.8 2.7 2.6 2.5 2.4 X : parts per Million : Proton

[9]

[15]

1.9 1.8

1.7

1.6 1.5

1.4 1.3

1.2 1.1 1.0

0.9 0.8

0.7

b

[35]

[38]

[40]

0.6

[37]

[36]

[39]

[41]

4.1 4.0 X : parts per Million : Proton

3.9

3.8

3.7

3.6

3.5

c

3.4

3.3

3.2

3.1

3.0

[53][52] [55] [49]

[57] [63]

[60] [58]

[54]

[66]

[73] [72]

[65] [64]

[70]

[71]

[69]

[62]

[59]

[47]

[51] [48] [50]

[46]

[45] [42]

[44]

[56]

[68]

8.4 8.3 8.2 8.1 X : parts per Million : Proton

[43]

[61]

[67]

8.0

7.9

7.8

7.7

7.6

7.5

7.4

7.3

7.2

7.1

7.0

6.9

6.8

6.7

6.6

Fig. 20.1 (a), (b) and (c), Expanded 0.60–3.00, 3.00–4.15 and 6.50–8.50 ppm regions, respectively, of the 600 MHz 1H NMR profile of a urine sample collected from a T2D patient receiving metformin treatment. Spectra acquired revealed that this patient was also taking paracetamol as an analgesic. Signals attributable to urea and water removed.

20

‘State-of-the-Art’ Metabolomics Investigations of Type 2 Diabetes

with those of other investigations. A full listing of significant 1H NMR-detectable metabolites identified is also observed in the urinary profiles (Table 20.1).

Disturbed Metabolic Pathways Involved in T2D Pathogenicity Energy metabolism, i.e. the tricarboxylic acid cycle or Krebs cycle (TCA), is unsurprisingly altered and this can be observed by metabolic changes in lactate, for example. Other disturbed pathways in saliva, urine and plasma include glycolysis, for example, pyruvate levels. However, these markers are not specific to T2D and are featured markers of many other diseases. Lipid metabolism and amino acid metabolism are also observed to be modified in T2D chemopathogenesis. High levels of ketones are observed in T2D, which arise from the use of lipids as a source of body fuel rather than glucose, and also from the deamination of amino acids.

275

Diabetic ketoacidosis arises from such elevated blood plasma ketone bodies. BCAAs, e.g. isoleucine and leucine, are also elevated in diabetes and are ascribable to a lack of uptake of energy sources, a further impairment of metabolic control (Suhre et al. 2010).

Personal Experience: Retrospective Network Pathway Analysis of Published Data Using MetExplore in a qualitative context, we aimed to identify the possible metabolic sub-networks involved in the pathophysiology of T2D (Cottret et al. 2018). Based on this analysis, the predominant pathways involved in T2D are those involved in the biosynthesis and/or metabolism of amino acids, specifically BCAA metabolism; phenylalanine and tryptophan metabolism; tyrosine biosynthesis; alanine, aspartate and glutamate metabolism; glycine, serine and threonine metabolism; and arginine biosynthesis.

ä Fig. 20.1 (continued) Assignments: [1] Unassigned Isopropyl-CH(CH3)2 function; [2] 2-Hydroxyisovalerate-δ-CH3; [3] 2-Hydroxybutyrate-CH3; [4] Isoleucine-CH3; [5] Leucine-CH3; [6] and [7] Valine-CH3s; [8] Methylsuccinate-CH3; [9] 2-Oxoisovalerate-CH3s; [10] 3-Aminoisobutyrate-CH3; [11] isobutyrate-CH3s; [12] 3-D-Hydroxybutyrate-CH3; [13] 2,2-Dimethyl succinate-CH3s; [14] Lactate-CH3; [15] Acetoin-CH3; [X] Alanine-CH3; [16] 2-Hydroxyglutarate1/2-CH2; [17] Acetate-CH3; [18] 2-Hydroxyglutarate-1/2-CH2; [19] N-Acetyl-CH3 functions of N-acetyl sugars, N-acetylamino acids (sharp resonances) and carbohydrate side-chain residues of trace level urinary N-acetylated glycoproteins (broader resonances); [20] -NHCOCH3 protons of paracetamol and its L-cysteinyl metabolite; [21] -NHCOCH3 protons of paracetamol glucuronide metabolite; [22] -NHCOCH3 protons of paracetamol sulphate metabolite; [23] 2-Hydroxyglutarate-1/2-CH2; [24] Acetone-CH3; [25] 2-Hydroxyglutarate-1/2-CH2; [26] OxaloacetateCH3; [P] Pyruvate-CH3; [27] Glutamine-γ-CH2; [28] Succinate-CH2s; [29] 3-Hydroxymethylglutarate-1/2-CH2; [30] Methylamine-N-CH3; [31] Citrate-CH2A/B; [32] Dimethylamine-N(CH3)2; [33] Trimethylamine-CH3; [34] Dimethylglycine-N(CH3)2; [35] Metformin-N-CH3; [36] Creatinine/Creatine-N-CH3; [37], [38] and [40] GlucoseC2-C6H ring protons; [39] Dimethylglycine-CH2; [41] Creatinine-CH2; [42] Unassigned; [43] Unassigned; [44] Tyrosine aromatic ring (Ar)-H; [45] Paracetamol-Ar-H; [46] Xanthurenate-Ar-H [47] and [53] Paracetamol glucuronide metabolite Ar-H ([53] also Indoxyl sulphate-Ar-H); [48] and [49] Indoxyl sulphate-Ar-H; [50] Tyrosine-Ar-H; [51] Indoxyl sulphate-Ar-H; [52] and [55] Paracetamol sulphate metabolite-Ar-H; [54] Phenylglycine-Ar-CH and Benzoate-Ar-CH; [56] Indoxyl sulphate-Ar-CH; [57] Hippurate-Ar-CH; [58] Hippurate-Ar-CH; [59] 1-Methylhistidine imidazole ring (IR)-CH; [60] Indoxyl sulphate-Ar-CH; [61] Xanthine-Ar-CH; [62] 4-Hydroxybenzoate-Ar-CH; [63] Hippurate-CH; [64] Quinolinate-Ar-CH; [H] Histidine AR-CH; [65] 6-Hydroxynicotinate-Ar-CH; [66] Trigonelline-Ar-CH; [67] Imidazole-IR-CH; [68] Hypoxanthine-C2/C7-CH; [69] and [72] 1-Methyladenine-Ar-CH; [70] Nicotinate-Ar-CH; [71] Unassigned; [73] Formate-CH

B. Percival et al.

2.0

1.0

0

abundance 0.1 0.3

276

Citrate-CH

Y : parts per Million : Proton 7.0 6.0 5.0

4.0

3.0

β-Glucose-C1H

α-Glucose-C1H

7.0 6.0 X : parts per Million : Proton

5.0

4.0

3.0

2.0

1.0

0 0 0.1 0.2 0.3 abundance

Fig. 20.2 2D 1H-1H NMR correlation spectroscopy (COSY) analysis of a T2D urine sample acquired using a 600 MHz facility (De Montfort University, Leicester, UK). Samples were prepared using 450 μL of urine, 50 μL of D2O with TSP (0.5% (w/v)), 50 μL of sodium azide solution (0.04% (w/v)) and 50 μL of phosphate

buffer solution (1.00 mol./L). Two clear connections are observed in the 2D NMR spectral profile ascribable to αand β-Glucose-C1H resonances at δ ¼ 5.21 and 4.65 ppm, respectively. 1D projections are observable on the x- and y-axis

Further pathways featured are the biosynthesis of carbohydrates, glyoxylate and dicarboxylate metabolism and 2-oxocarboxylic acid metabolism. Figure 20.3 highlights the relationship between these pathways by displaying a sub-network using the lightest path algorithm, which forms the lightest paths between each pair of blood serum metabolites available in Table 20.1, and allows visualisation of metabolic paths between pairs of elements of interest. The metabolic pathways highlighted in Fig. 20.3 are consistent with previous studies performed. For example, disturbances in BCAA metabolism have been demonstrated to arise from impaired insulin resistance (Zhao et al. 2016). Sun et al. (2019) also found alanine, aspartate and glutamate metabolism, glycine, serine and

threonine metabolism and phenylalanine, tyrosine and tryptophan biosynthesis to be significant ( p40% (Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) 2012). The CHARM trial confirms an adjusted hazard ratio of 1.31 for all-cause mortality per 10% reduction in LVEF 25 kg/m2 signal risk, which seems higher for HFpEF than HFrEF (Pandey et al. 2017). Among postmenopausal women, excessive adiposity was related with HFpEF only, not HFrEF, particularly for African American women. Hypertension (40.9%) and obesity (25.8%), were the paramount prognostic markers (Eaton et al. 2016). In contrast, higher BMI indicated lower risk of symptomatic HF in another series, different from waist-to-height ratio (WHR), which was a positive prognostic marker for the composite outcome (Chandramouli et al. 2019). Low BMI paired with high WHR had a more ominous course than elevated BMI and normal WHR (Chandramouli et al. 2019).

Possible Involved Pathways and Biomolecules Obesity is strongly related with systemic arterial hypertension, diabetes, insulin resistance, metabolic syndrome, and obstructive sleep apnea, all of which contribute to the development of HF. On the other hand, reduced cardiorespiratory fitness in HF patients could be the cause of obesity and therefore the “circulus vitiosus” is difficult to interrupt. Obesity induces hemodynamic, structural, neurohormonal changes, and systemic inflammation that induce functional and structural cardiac remodeling (Fig. 31.1), including HFpEF, and its impact on outcome in HFrEF patients is significant. However, the influence of obesity on HFmrEF is less clear. The hemodynamic changes in obesity consider elevated central blood volume, reduced systemic

430

M. Tadic and C. Cuspidi

Left ventricular remodeling Interstitial fibrosis Pulmonary hypertension

Right ventricular remodeling Dilated left atrium

HFpEF

OBESITY

induces elevated venous returns to the pulmonary Peptides, cytokines, Hemodynamic shifts, oxidative stress sympathetic imbalance circulation. Dyspnea becomes common in such

Fig. 31.1 Local and systemic changes associated with obesity

vascular resistance and stroke volume, and ultimately elevated cardiac output proportional to the degree of obesity but not to body surface area (Carbone et al. 2017; Tadic and Cuspidi 2019) (Fig. 31.1). Lean (fat-free) mass in obese patients is one of the most important parameters responsible for the development of a hyperdynamic state. Heart rate is only slightly increased; thus, cardiac output follows elevations of left ventricular (LV) stroke volume. Cardiac effort, and particularly LV effort, in obese patients exceeds predicted values due to elevated LV stroke work. LV end-diastolic pressure and pulmonary capillary wedge pressure are commonly elevated in moderate-to-severe body adiposity. The persistent increase in cardiac output due to elevated preload induces an initial LV dilatation, according to the Frank-Starling law, followed by a compensatory hypertrophic response confirmed at the cellular and organ level. LV hypertrophy represents a compensatory mechanism to decrease wall stress and oxygen demand according to LaPlace’s law. Pulmonary artery pressure is often increased due to LV failure, and retrograde transmission of increased LV filling pressure over pulmonary veins to pulmonary circulation, resulting in the increase of pulmonary vascular resistance particularly in those with sleep apnea or pulmonary hypoventilation (Alpert et al. 2018). RV filling pressure is frequently increased, which further

context. At the beginning, increased LV filling pressures and impairment in LV diastolic function were considered as the result of LV hypertrophy. However, studies found that obese patients may have LV diastolic dysfunction without LV hypertrophy (Dote et al. 2012; Russo et al. 2011), which indicates that some other mechanisms of LV remodeling besides LV hypertrophy may be involved (Fig. 31.1). LV hypertrophy could be even a protective response in face of increased preload by reduction of wall stress. Obese patients with HFpEF had increased relative wall thickness and smaller cardiac volumes even in the absence of increased LV mass, which demonstrates LV concentric remodeling (Yagmur et al. 2017; Zile et al. 2011).

Anthropometric Measurements The visceral adipose tissue points toward decreased cardiac output and increased systemic vascular resistance, with opposite correlations for lower body fat. Abdominal subcutaneous fat seems to play a secondary role regarding LV concentric remodeling, only visceral adipose tissue being relevant (Shah et al. 2014). LV hypertrophy and LV mass have strong links with excessive body weight, eccentric hypertrophy being more common than the concentric phenotype (Neeland et al. 2013).

Other Heart Chambers Right ventricular (RV) remodeling assessment by echocardiography is challenging in obese patients due to the position of the RV in the chest and increased thickness of chest wall, yet reduced function without overt heart disease has been perceived (Cuspidi et al. 2014), including larger volume and mass (Wong et al. 2006). Left atrial

31

Heart Failure and the Obesity Paradox

(LA) dilatation, connected with HFpEF, has also been linked to elevated adiposity (Chahal et al. 2012). LA volume seems to follow visceral, yet not subcutaneous abdominal fat (Chahal et al. 2012). LA function and mechanics can deteriorate as well in HFpEF (Oliver et al. 2017).

Biohumoral and Neurohormonal Changes Activation of the renin-angiotensin-aldosterone and the sympathetic nervous system, natriuretic peptide, systemic inflammation, and oxidative stress are reported. Cytokines such as interleukin (IL) 1 beta, tumor necrosis factor alpha, and IL-1 alpha, experimentally induce diastolic dysfunction (Van Tassell et al. 2013; O’Brien et al. 2014), and anti-inflammatory could ameliorate HFpEF and HFrEF. An IL-1 receptor antagonist improved cardiorespiratory fitness in patients with HFrEF and HFpEF, with increase of peak oxygen consumption (Van Tassell et al. 2012, 2014). All these mechanisms might induce cardiac interstitial fibrosis that further decreases cardiac elasticity and compliance, and subsequently increases energy consumption during LV diastole—an extremely energy-demanding process. Moreover, these biohumoral and neurohormonal mechanisms promote enhanced atherosclerosis, which also may induce HF.

Obesity Paradox In addition to an excess of fat mass, obese patients usually also have more lean mass. Patients with heart failure with increased amount of lean mass showed better cardiopulmonary fitness, a major determinant of clinical outcomes in the general population, and therefore lower mortality risk, which could be related to the “obesity paradox” phenomenon. Elevated lean mass represents a stronger predictor in heart failure in comparison

431

with fat mass, whereas elevated fat mass in patients with coronary heart disease could have protective effects when fat mass is not related with increased systemic inflammation (Carbone et al. 2019). Obese patients with decreased amount of lean mass, despite increased BMI and fat mass, namely, sarcopenic obesity, suffer increased mortality. This suggests that lean mass plays a key role, and therefore exercise training and dietary interventions could represent important strategies.

Cardiovascular Mortality The “obesity paradox” does not reduce risk in morbidly obese patients, only in mildly overweight cases. Nevertheless, there is still no agreement regarding the U-shape relationship between BMI and mortality or risk for HF development (Table 31.1). Mildly overweight patients had the lowest rates of death or cardiovascular hospitalization (Haass et al. 2011), and absence of obesity was an independent predictor of mortality in both HFpEF and HFrEF (Ather et al. 2012). On the other hand, Mohammed et al. reported that obesity was related with better outcome after adjustment for age, sex, and other comorbidities, and this association did not show U-shape (Mohammed et al. 2012). BMI < 30 kg/m2 pointed toward less 30-day mortality for HFpEF in one experience (PowellWiley et al. 2018). A modest association was found in HFrEF subjects, with no risk increase when BMI > 30 kg/m2. The “obesity paradox“was not present in HFpEF (Table 31.1). In another series, lack of obesity was related with mortality in HFpEF and HFrEF (Iorio et al. 2018). Further confirmation that mortality risk had a U-shaped form in both HFpEF and HFrEF is available, however, with the nadir at 30.0–34.9 kg/m2 (Padwal et al. 2014). One potential mechanism that could explain the “obesity paradox” is adiponectin, an adipocyte-specific cytokine, inversely related

432

M. Tadic and C. Cuspidi

Table 31.1 The association between obesity paradox and HFpEF Sample size 4109 patients

HFpEF/ HFrEF HFpEF

Ather et al. (2012)

942 patients

HFpEF/ HFrEF

2-year follow-up

Powell-Wiley et al. (2018)

39,647 patients

HFpEF/ HFrEF

30-day and 1-year follow-up

Iorio et al. (2018)

2314 patients

HFpEF/ HFrEF

31-month follow-up

Padwal et al. (2014)

23,967 subjects

HFpEF/ HFrEF

Meta-analysis (3-year follow-up)

Refs. I-PRESERVE (2011)

Study type Follow-up (4 years)

Main findings Overweight was related with lower mortality Or cardiovascular hospitalization. Underweight And severely overweight patients had higher Mortality rates than overweight Nonobese patients had higher mortality in HFpEF and HFrEF patients The obesity paradox for 30-day mortality Existed at all BMI levels only in HFrEF patients Nonobese patients had higher overall mortality In HFpEF and HfrEF patients and mortality rate Between these groups was similar U-shaped form of relationship between mortality And BMI was found in HFpEF and HFrEF patients With highly positioned nadir at 30.0–34.9 kg/m2

BMI body mass index, HFpEF heart failure with preserved ejection fraction, HFrEF heart failure with reduced ejection fraction

with BMI in HF patients. Lower adiponectin levels are associated with increased mortality, which means that patients with increased BMI have higher adiponectin and lower mortality. The other mechanisms of “obesity paradox” involve anti-inflammatory effects of elevated lipoproteins, and decreased response of the renin-angiotensin-aldosterone system.

patients usually have lower systemic vascular resistance, particularly if they do not exhibit arterial hypertension (Alpert et al. 2014; Lavie et al. 2009). Afterload reduction results in improved forward flow and better cardiac output.

Recommended Lines for Further Investigation Risks of Bias in the Interpretation of the Paradox HF is characterized by decreased and/or inadequate cardiac output and elevated systemic vascular resistance, which is why the obese patients with preserved skeletal muscle mass have a better prognosis than HF patients with reduced lean mass, independent of stroke volume and cardiac output (Yancy et al. 2013). Furthermore, obese

Large randomized studies that evaluate intentional weight loss are still missing. Investigation of the impact of fat mass and lean mass on HF occurrence and outcome should be encouraged. It might be reasonable to hypothesize that increase of lean mass would be associated with greater muscular strength and better cardiorespiratory fitness, which altogether improve outcome in HF patients.

31

Heart Failure and the Obesity Paradox

References Alpert MA, Lavie CJ, Agrawal H, Aggarwal KB, Kumar SA (2014) Obesity and heart failure: epidemiology, pathophysiology, clinical manifestations, and management. Transl Res 164(4):345–356 Alpert MA, Karthikeyan K, Abdullah O, Ghadban R (2018) Obesity and cardiac remodleing in adults: mechanisms and clinical implications. Prog Cardiovasc Dis 61(2):114–123 Ather S, Chan W, Bozkurt B, Aguilar D, Ramasubbu K, Zachariah AA, Wehrens XH, Deswal A (2012) Impact of non-cardiac comorbidities on morbidity and mortality in a predominantly male population with heart failure and preserved versus reduced ejection fraction. J Am Coll Cardiol 59(11):998–1005 Baena-Díez JM, Byram AO, Grau M et al (2010) Obesity is an independent risk factor for heart failure: zona Franca cohort study. Clin Cardiol 33(12):760–764 Benjamin EJ, Virani SS, Callaway CW, Chamberlain AM, Chang AR, Cheng S, Chiuve SE, Cushman M, Delling FN, Deo R, de Ferranti SD, Ferguson JF, Fornage M, Gillespie C, Isasi CR, Jiménez MC, Jordan LC, Judd SE, Lackland D, Lichtman JH, Lisabeth L, Liu S, Longenecker CT, Lutsey PL, Mackey JS, Matchar DB, Matsushita K, Mussolino ME, Nasir K, O’Flaherty M, Palaniappan LP, Pandey A, Pandey DK, Reeves MJ, Ritchey MD, Rodriguez CJ, Roth GA, Rosamond WD, UKA S, Satou GM, Shah SH, Spartano NL, Tirschwell DL, Tsao CW, Voeks JH, Willey JZ, Wilkins JT, Wu JH, Alger HM, Wong SS, Muntner P, American Heart Association Council on Epidemiology and Prevention Statistics Committee and Stroke Statistics Subcommittee (2018) Heart disease and stroke statistics-2018 update: a report from the American Heart Association. Circulation 137(12): e67–e492 Bhatia RS, Tu JV, Lee DS, Austin PC, Fang J, Haouzi A, Gong Y, Liu PP (2006) Outcome of heart failure with preserved ejection fraction in a population-based study. N Engl J Med 355:260–269 Carbone S, Lavie CJ, Arena R (2017) Obesity and heart failure: focus on the obesity paradox. Mayo Clin Proc 92(2):266–279 Carbone S, Canada JM, Billingsley HE, Siddiqui MS, Elagizi A, Lavie CJ (2019) Obesity paradox in cardiovascular disease: where do we stand? Vasc Health Risk Manag 15:89–100 Chahal H, McCleland RL, Tandai H, Jain A, Turkbey EB, Hundley WG, Barr RG, Kizer J, Lima JAC, Bluemke DA, Kawut SM (2012) Obesity and right ventricular structure and function: the MESA-right ventricle study. Chest 141:388–395 Chandramouli C, Tay WT, Bamadhaj NS, Tromp J, Teng TK, Yap JJL, MacDonald MR, Hung CL, Streng K, Naik A, Wander GS, Sawhney J, Ling LH, Richards AM, Anand I, Voors AA, Lam CSP, ASIAN-HF Investigators (2019) Association of obesity with heart

433 failure outcomes in 11 Asian regions: a cohort study. PLoS Med 16(9):e1002916 Cheng RK, Cox M, Neely ML, Heidenreich PA, Bhatt DL, Eapen ZJ, Hernandez AF, Butler J, Yancy CW, Fonarow GC (2014) Outcomes in patients with heart failure with preserved, borderline, and reduced ejection fraction in the Medicare population. Am Heart J 168:721–730 Coles AH, Fisher K, Darling C, Yarzebski J, McManus DD, Gore JM, Lessard D, Goldberg RJ (2014) Longterm survival for patients with acute decompensated heart failure according to ejection fraction findings. Am J Cardiol 114:862–868 Cuspidi C, Rescaldani M, Sala C, Grassi G (2014) Leftventricular hypertrophy and obesity: a systematic review and meta-analysis of echocardiographic studies. J Hypertens 32(1):16–25 Dote K, Miyasaka Y, Tsujimoto S et al (2012) Obesity as an independent risk for left ventricular diastolic dysfunction in 692 Japanese patients. Obes Res Clin Pract 6(3):e175–e262 Eaton CB, Pettinger M, Rossouw J, Martin LW, Foraker R, Quddus A, Liu S, Wampler NS, Hank Wu WC, Manson JE, Margolis K, Johnson KC, Allison M, Corbie-Smith G, Rosamond W, Breathett K, Klein L (2016) Risk factors for incident hospitalized heart failure with preserved versus reduced ejection fraction in multiracial cohort of postmenopausal women. Circ Heart Fail 9(10):e002883 Fonarow GC, Stough WG, Abraham WT, Albert NM, Gheorghiade M, Greenberg BH, O’Connor CM, Sun JL, Yancy CW, Young JB, OPTIMIZE-HF Investigators and Hospitals (2007) Characteristics, treatments, and outcomes of patients with preserved systolic function hospitalized for heart failure: a report from the OPTIMIZE-HF registry. J Am Coll Cardiol 50:768–777 Haass M, Kitzman DW, Anand IS, Miller A, Zile MR, Massie BM et al (2011) Body mass index and adverse cardiovascular outcomes in heart failure patients with preserved ejection fraction: results from the Irbesartan in heart failure with preserved ejection fraction (I-PRESERVE) trial. Circ Heart Fail 4:324–331 Iorio A, Senni M, Barbati G, Greene SJ, Poli S, Zambon E, Di Nora C, Cioffi G, Tarantini L, Gavazzi A, Sinagra G, Di Lenarda A (2018) Prevalence and prognostic impact of non-cardiac co-morbidities in heart failure outpatients with preserved and reduced ejection fraction: a community-based study. Eur J Heart Fail 20 (9):1257–1266 Kenchaiah S, Evans JC, Levy D et al (2002) Obesity and the risk of heart failure. N Engl J Med 347(5):305–313 Lavie CJ, Milani RV, Ventura HO (2009) Obesity and cardiovascular disease: risk factor, paradox, and impact of weight loss. J Am Coll Cardiol 53(21):1925–1932 Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) (2012) The survival of patients with heart failure with preserved or reduced left ventricular

434 ejection fraction: an individual patient data metaanalysis. Eur Heart J 33:1750–1757 Mohammed SF, Borlaug BA, Roger VL, Mirzoyev SA, Rodeheffer RJ, Chirinos JA, Redfield MM (2012) Comorbidity and ventricular and vascular structure and function in heart failure with preserved ejection fraction: a community-based study. Circ Heart Fail 5 (6):710–719 Neeland IJ, Gupta S, Ayers CR, Turer AT, Rame JE, Das SR, Berry JD, Khera A, McGuire DK, Vega GL, Grundy SM, de Lemos JA, Drazner MH (2013) Relation of regional fat distribution to left ventricular structure and function. Circ Cardiovasc Imaging 6:800–807 O’Brien LC, Mezzaroma E, Van Tassell BW et al (2014) Interleukin-18 as a therapeutic target in acute myocardial infarction and heart failure. Mol Med 20:221–229 Oliver W, Matthews G, Ayers CR, Garg S, Gupta S, Neeland IJ, Drazner MH, Berry JD, Matulevicius S, de Lemos JA (2017) Factors associated with left atrial remodeling in the general population. Circ Cardiovasc Imaging 10(2):e005047 Padwal R, McAlister FA, McMurray JJ, Cowie MR, Rich M, Pocock S, Swedberg K, Maggioni A, Gamble G, Ariti C, Earle N, Whalley G, Poppe KK, Doughty RN, Bayes-Genis A, Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) (2014) The obesity paradox in heart failure with patients with preserved versus reduced ejection fraction: a meta-analysis of individual patient data. Int J Obes 38 (8):1110–1114 Pandey A, LaMonte M, Klein L, Ayers C, Psaty BM, Eaton CB, Allen NB, de Lemos JA, Carnethon M, Greenland P, Berry JD (2017) Relationship between physical activity, body mass index, and risk of heart failure. J Am Coll Cardiol 69(9):1129–1142 Pocock SJ, Ariti CA, McMurray JJ et al (2013) Predicting survival in heart failure: a risk score based on 39 372 patients from 30 studies. Eur Heart J 34:1404–1413 Ponikowski P, Voors AA, Anker SD, Bueno H, Cleland JGF, Coats AJS, Falk V, González-Juanatey JR, Harjola VP, Jankowska EA, Jessup M, Linde C, Nihoyannopoulos P, Parissis JT, Pieske B, Riley JP, Rosano GMC, Ruilope LM, Ruschitzka F, Rutten FH, van der Meer P, ESC Scientific Document Group (2016) 2016 ESC guidelines for the diagnosis and treatment of acute and chronic heart failure: the task force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC)developed with the special contribution of the heart failure association (HFA) of the ESC. Eur Heart J 37(27):2129–2200 Powell-Wiley TM, Ngwa J, Kebede S, Lu D, Schulte PJ, Bhatt DL, Yancy C, Fonarow GC, Albert MA (2018) Impact of body mass index on heart failure by race/ ethnicity from the get with the guidelines-heart failure (GWTG-HF) registry. JACC Heart Fail 6(3):233–242 Russo C, Jin Z, Homma S et al (2011) Effect of obesity and overweight on left ventricular diastolic function: a

M. Tadic and C. Cuspidi community based study in an elderly cohort. J Am Coll Cardiol 57(12):1368–1374 Savji N, Meijers WC, Bartz TM, Bhambhani V, Cushman M, Nayor M, Kizer JR, Sarma A, Blaha MJ, Gansevoort RT, Gardin JM, Hillege HL, Ji F, Kop WJ, Lau ES, Lee DS, Sadreyev R, van Gilst WH, Wang TJ, Zanni MV, Vasan RS, Allen NB, Psaty BM, van der Harst P, Levy D, Larson M, Shah SJ, de Boer RA, Gottdiener JS, Ho JE (2018) The association of obesity and cardiometabolic traits with incident HFpEF and HFrEF. JACC Heart Fail 6 (8):701–709 Senthong V, Kirsop JL, Tang WH (2017) Clinical phenotyping of heart failure with biomarkers: current and future perspectives. Curr Heart Fail Rep 14 (2):106–116 Shah AM, Shah SJ, Anand IS, et al; TOPCAT investigators (2014) Cardiac structure and function in heart failure with preserved ejection fraction: baseline findings from the echocardiographic study of the treatment of preserved cardiac function heart failure with an aldosterone antagonist trial. Circ Heart Fail 7 (1):104–115 Solomon SD, Anavekar N, Skali H et al (2005) Influence of ejection fraction on cardiovascular outcomes in a broad spectrum of heart failure patients. Circulation 112:3738–3744 Steinberg BA, Zhao X, Heidenreich PA, Peterson ED, Bhatt DL, Cannon CP, Hernandez AF, Fonarow GC, Get With the Guidelines Scientific Advisory Committee and Investigators (2012) Trends in patients hospitalized with heart failure and preserved left ventricular ejection fraction: prevalence, therapies, and outcomes. Circulation 126:65–75 Sweitzer NK, Lopatin M, Yancy CW, Mills RM, Stevenson LW (2008) Comparison of clinical features and outcomes of patients hospitalized with heart failure and normal ejection fraction (> or.55%) versus those with mildly reduced (40% to 55%) and moderately to severely reduced (30 mg/g), or a reduction of kidney function (estimated glomerular filtration rate [eGFR] 40 kg/m2 (Sturm and Hattori 2013). Osteoarthritis (OA) is also highly prevalent. It is estimated that 25.9% of the projected total adult population will have doctordiagnosed arthritis by 2040 (Hootman et al. 2016). The lifetime risk of end-stage knee osteoarthritis alone is 13.3% for men and 18.8% for women (Ogden et al. 2014). Knee OA is the second most prevalent cause of disability in the world (GBD 2016 Disease and Injury Incidence and Prevalence Collaborators 2017). The risk of OA-associated disability is as elevated as of cardiac conditions (Wang et al. 2016) and is the most prevalent of all diseases in the elderly (Yokota et al. 2015). In terms of hospital charges,

K. M. Mellion and S. N. Kothari

osteoarthritis is more expensive than pneumonia, stroke, or complications from diabetes (Teichtahl et al. 2009). Obesity is an independent risk factor for osteoarthritis (Gu et al. 2019). Patients with grade II obesity have 4.7 times the likelihood of developing knee osteoarthritis compared to those with normal weights (Reyes et al. 2016). Research suggests this risk is due to both biomechanical and systemic inflammatory effects on joints (Koonce and Bravman 2013). These effects eventually lead to total joint arthroplasty (TJA) in an increasing number of patients with obesity (Belmont et al. 2014; Fehring et al. 2007; Kremers et al. 2014). In the United States, over one million total knee and total hip replacement procedures are performed yearly. Patients with obesity are known to have a higher risk of complications for total joint arthroplasty (Salih and Sutton 2013; Belmont et al. 2014). The American Association of Hip and Knee Surgeons suggests weight loss prior to TJA for patients with BMI >40 kg/m2 (Workgroup of the American Association of Hip and Knee Surgeons Evidence-Based Committee 2013). While diet and exercise are important for a healthy lifestyle, these methods will not achieve a significant sustained weight loss. Bariatric surgery has been shown to provide sustained weight loss, as well as resolution of many obesity-related comorbidities, including type II diabetes, gastroesophageal reflux, and hyperlipidemia (Sharples and Mahawar 2019). Data investigating the effect of prior bariatric surgery on postoperative TJA outcomes is mixed.

Impact of Obesity on Lower Limb Osteoarthritis In the United States, 31% of those with obesity were diagnosed with arthritis, while only 16% of normal weight individuals carried the diagnosis (Center for Disease Control and Prevention 2018). Obesity has been shown to be an independent risk factor for osteoarthritis (Gu et al. 2019). In a Swedish study by Jarvholm et al.,

60

The Role of Obesity and Bariatric Surgery in the Management of Knee and Hip Osteoarthritis

15–67 year-old male construction workers were found to be more likely to undergo knee or hip replacement as BMI increased, even when controlling for age and tobacco use (Jarvholm et al. 2008). Data from the Nurses’ Health Study, which included over 121,000 female nurses, revealed those with a BMI >35 kg/m2 were twice as likely to undergo total hip arthroplasty (THA) compared to those with BMI 40 kg/m2 who undergo TJA, there is only one complication for every 14 complication-free operations. These authors suggested not using a strict BMI cutoff for patients who otherwise qualify for TJA. Similarly, Springer et al. followed 289 patients with BMI >40 kg/m2 and end-stage osteoarthritis for 2 years. They found that requiring weight loss prior to TJA in this population most often leads to these patients remaining morbidly obese and never undergoing TJA. Only 20% of patients underwent bariatric surgery. These authors suggested increasing the resources and coordinated care to facilitate patients’ weight loss (Giori et al. 2018).

Ongoing Trials and Future Perspectives There is currently no consensus on the utility of bariatric surgery for weight loss prior to TJA, and no prospective or randomized controlled trials on the topic. In addition, no prospective studies have evaluated whether reduced biomechanical strain on lower extremity joints after bariatric surgery eliminates the need for TJA in certain patients, or if, conversely, the increased mobility and exercise capability of patients who lose significant weight

60

The Role of Obesity and Bariatric Surgery in the Management of Knee and Hip Osteoarthritis

from bariatric surgery lead to an increase in TJA in this population. The Surgical Weight-Loss to Improve Functional Status Trajectories Following TKA (SWIFT) Trial (NCT02598531) is the first prospective, controlled, multicenter trial comparing postoperative outcomes in patients with severe obesity who undergo TKA with a wellmatched cohort of patients who undergo weight loss surgery prior to elective TKA. This trial is currently recruiting patients (Surgical WeightLoss to Improve Functional Status Trajectories Following Total Knee Arthroplasty/SWIFT Trial n.d.) (Benotti et al. 2018).

Future Directions Important areas for study include: comparing the effects of surgical weight loss and medical weight loss on TJA necessity and outcome, comparing the effect of different surgical weight loss procedures on TJA necessity and outcome, investigating risk stratification protocols for patients with obesity and end-stage osteoarthritis, determining a safe and cost-effective BMI cutoff for TJA, and ultimately determining an appropriate weight management algorithm and multidisciplinary approach for obese patients with end-stage osteoarthritis. In addition to studies investigating the effect of bariatric surgery on osteoarthritis and TJA outcomes, further investigation into the mechanisms that regulate peripheral and central adipokine activity and their contribution to the development of osteoarthritis may lead to novel treatments for osteoarthritis in the morbidly obese population.

References Abdel MP, Bonadurer GF 3rd, Jennings MT, Hanssen AD (2015) Increased aseptic tibial failures in patients with a BMI >/¼35 and well-aligned total knee arthroplasties. J Arthroplast 30(12):2181–2184. https://doi.org/10.1016/j.arth.2015.06.057 Barrett M, Prasad A, Boyce L, Dawson-Bowling S, Achan P, Millington S, Hanna SA (2018) Total hip

823

arthroplasty outcomes in morbidly obese patients: a systematic review. EFORT Open Rev 3(9):507–512. https://doi.org/10.1302/2058-5241.3.180011 Belmont PJ Jr, Goodman GP, Waterman BR, Bader JO, Schoenfeld AJ (2014) Thirty-day postoperative complications and mortality following total knee arthroplasty: incidence and risk factors among a national sample of 15,321 patients. J Bone Joint Surg Am 96(1):20–26. https://doi.org/10.2106/JBJS.M. 00018 Benotti PN, Still CD, Craig Wood G, Seiler JL, Seiler CJ, Thomas SP, Petrick AT, Suk M, Irving BA, SWIFT Trial Investigators (2018) Surgical weight-loss to improve functional status trajectories following total knee arthroplasty: SWIFT trial: rationale, design, and methods. Contemp Clin Trials 69:1–9 Bergmann G, Deuretzbacher G, Heller M, Graichen F, Rohlmann A, Strauss J, Duda GN (2001) Hip contact forces and gait patterns from routine activities. J Biomech 34(7):859–871. https://doi.org/10.1016/ s0021-9290(01)00040-9 Centers for Disease Control and Prevention (2018) Arthritis-related statistics. U.S. Department of Health & Human Services. https://www.cdc.gov/arthritis/ data_statistics/arthritis-related-stats.htm. Accessed December 20 2019 Chee YH, Teoh KH, Sabnis BM, Ballantyne JA, Brenkel IJ (2010) Total hip replacement in morbidly obese patients with osteoarthritis: results of a prospectively matched study. J Bone Joint Surg Br 92 (8):1066–1071. https://doi.org/10.1302/0301-620X. 92B8.22764 Chen SX, Bomfim FA, Youn HA, Ren-Fielding C, Samuels J (2018) Predictors of the effect of bariatric surgery on knee osteoarthritis pain. Semin Arthritis Rheum 48(2):162–167. https://doi.org/10.1016/j. semarthrit.2018.02.001 Chu IJH, Lim AYT, Ng CLW (2018) Effects of meaningful weight loss beyond symptomatic relief in adults with knee osteoarthritis and obesity: a systematic review and meta-analysis. Obes Rev 19 (11):1597–1607. https://doi.org/10.1111/obr.12726 Culler SD, Jevsevar DS, Shea KG, McGuire KJ, Wright KK, Simon AW (2016) The incremental hospital cost and length-of-stay associated with treating adverse events among medicare beneficiaries undergoing THA during fiscal year 2013. J Arthroplast 31 (1):42–48. https://doi.org/10.1016/j.arth.2015.07.037 Dumond H, Presle N, Terlain B, Mainard D, Loeuille D, Netter P, Pottie P (2003) Evidence for a key role of leptin in osteoarthritis. Arthritis Rheum 48 (11):3118–3129. https://doi.org/10.1002/art.11303 Fehring TK, Odum SM, Griffin WL, Mason JB, McCoy TH (2007) The obesity epidemic: its effect on total joint arthroplasty. J Arthroplast 22(6 Suppl 2):71–76. https://doi.org/10.1016/j.arth.2007.04.014 Foran JR, Mont MA, Rajadhyaksha AD, Jones LC, Etienne G, Hungerford DS (2004) Total knee arthroplasty in obese patients: a comparison with a

824 matched control group. J Arthroplasty 19(7):817–824. https://doi.org/10.1016/j.arth.2004.03.017 Francisco V, Perez T, Pino J, Lopez V, Franco E, Alonso A, Gonzalez-Gay MA, Mera A, Lago F, Gomez R, Gualillo O (2018a) Biomechanics, obesity, and osteoarthritis. The role of adipokines: when the levee breaks. J Orthop Res 36(2):594–604. https:// doi.org/10.1002/jor.23788 Francisco V, Pino J, Campos-Cabaleiro V, RuizFernandez C, Mera A, Gonzalez-Gay MA, Gomez R, Gualillo O (2018b) Obesity, fat mass and immune system: role for leptin. Front Physiol 9:640. https:// doi.org/10.3389/fphys.2018.00640 Galea VP, Rojanasopondist P, Ingelsrud LH, Rubash HE, Bragdon C, Huddleston Iii JI, Malchau H, Troelsen A (2019) Longitudinal changes in patient-reported outcome measures following total hip arthroplasty and predictors of deterioration during follow-up: a sevenyear prospective international multicentre study. Bone Joint J 101-B(7):768–778 GBD 2016 Disease and Injury Incidence and Prevalence Collaborators Global, regional, and national incidence, prevalence, and years lived with disability for 328 diseases and injuries for 195 countries, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016. Lancet. 2017;390 (10100):1211–1259 Giori NJ, Amanatullah DF, Gupta S, Bowe T, Harris AHS (2018) Risk reduction compared with access to care: quantifying the trade-off of enforcing a body mass index eligibility criterion for joint replacement. J Bone Joint Surg Am 100(7):539–545. https://doi.org/ 10.2106/JBJS.17.00120 Griffin TM, Huebner JL, Kraus VB, Guilak F (2009) Extreme obesity due to impaired leptin signaling in mice does not cause knee osteoarthritis. Arthritis Rheum 60(10):2935–2944. https://doi.org/10.1002/ art.24854 Groen VA, van de Graaf VA, Scholtes VA, Sprague S, van Wagensveld BA, Poolman RW (2015) Effects of bariatric surgery for knee complaints in (morbidly) obese adult patients: a systematic review. Obes Rev 16 (2):161–170. https://doi.org/10.1111/obr.12236 Gu A, Cohen JS, Malahias MA, Lee D, Sculco PK, McLawhorn AS (2019) The effect of bariatric surgery prior to lower-extremity total joint arthroplasty: a systematic review. HSS J 15(2):190–200. https://doi.org/ 10.1007/s11420-019-09674-2 Hales CM, Carroll MD, Fryar CD, Ogden CL (2017) Prevalence of obesity among adults and youth: United States, 2015–2016. NCHS Data Brief, vol 288. National Center for Health Statistics, Hyattsville, MD Heywood S, McClelland J, Geigle P, Rahmann A, Villalta E, Mentiplay B, Clark R (2019) Force during functional exercises on land and in water in older adults with and without knee osteoarthritis: Implications for rehabilitation. Knee 26(1):61–72 Hootman JM, Helmick CG, Barbour KE, Theis KA, Boring MA (2016) Updated projected prevalence of self-reported doctor-diagnosed arthritis and arthritisattributable activity limitation among US adults,

K. M. Mellion and S. N. Kothari 2015–2040. Arthritis Rheumatol 68(7):1582–1587. https://doi.org/10.1002/art.39692 Inacio MC, Silverstein DK, Raman R, Macera CA, Nichols JF, Shaffer RA, Fithian D (2014) Weight patterns before and after total joint arthroplasty and characteristics associated with weight change. Perm J 18(1):25–31. https://doi.org/10.7812/TPP/13-082 Jamsen E, Nevalainen P, Eskelinen A, Huotari K, Kalliovalkama J, Moilanen T (2012) Obesity, diabetes, and preoperative hyperglycemia as predictors of periprosthetic joint infection: a single-center analysis of 7181 primary hip and knee replacements for osteoarthritis. J Bone Joint Surg Am 94(14):e101. https:// doi.org/10.2106/JBJS.J.01935 Jarvenpaa J, Kettunen J, Kroger H, Miettinen H (2010) Obesity may impair the early outcome of total knee arthroplasty. Scand J Surg 99(1):45–49. https://doi.org/ 10.1177/145749691009900110 Jarvholm B, From C, Lewold S, Malchau H, Vingard E (2008) Incidence of surgically treated osteoarthritis in the hip and knee in male construction workers. Occup Environ Med 65(4):275–278. https://doi.org/10.1136/ oem.2007.033365 Karlson EW, Mandl LA, Aweh GN, Sangha O, Liang MH, Grodstein F (2003) Total hip replacement due to osteoarthritis: the importance of age, obesity, and other modifiable risk factors. Am J Med 114(2):93–98. https://doi.org/10.1016/s0002-9343(02) 01447-x Karvonen-Gutierrez CA, Sowers MR, Heeringa SG (2012) Sex dimorphism in the association of cardiometabolic characteristics and osteophytes-defined radiographic knee osteoarthritis among obese and non-obese adults: NHANES III. Osteoarthr Cartil 20(7):614–621. https:// doi.org/10.1016/j.joca.2012.02.644 Kerkhoffs GM, Servien E, Dunn W, Dahm D, Bramer JA, Haverkamp D (2012) The influence of obesity on the complication rate and outcome of total knee arthroplasty: a meta-analysis and systematic literature review. J Bone Joint Surg Am 94(20):1839–1844. https://doi.org/10.2106/JBJS.K.00820 Koonce RC, Bravman JT (2013) Obesity and osteoarthritis: more than just wear and tear. J Am Acad Orthop Surg 21(3):161–169. https://doi.org/10.5435/JAAOS21-03-161 Kremers HM, Visscher SL, Kremers WK, Naessens JM, Lewallen DG (2014) The effect of obesity on direct medical costs in total knee arthroplasty. J Bone Joint Surg Am 96(9):718–724. https://doi.org/10.2106/ JBJS.M.00819 Lee GC, Ong K, Baykal D, Lau E, Malkani AL (2018) Does prior bariatric surgery affect implant survivorship and complications following primary total hip arthroplasty/total knee arthroplasty? J Arthroplast 33 (7):2070–2074 e2071. https://doi.org/10.1016/j.arth. 2018.01.064 Li S, Luo X, Sun H, Wang K, Zhang K, Sun X (2019) Does prior bariatric surgery improve outcomes following total joint arthroplasty in the morbidly obese? A Meta-Anal J Arthropl 34(3):577–585

60

The Role of Obesity and Bariatric Surgery in the Management of Knee and Hip Osteoarthritis

Liu JX, Paoli AR, Mahure SA, Bosco J 3rd, Campbell KA (2018) Preoperative bariatric surgery and the risk of readmission following total joint replacement. Orthopedics 41(2):107–114. https://doi.org/10.3928/ 01477447-20180226-02 Liu JX, Paoli AR, Mahure SA, Bosco J 3rd, Campbell KA (2019). Preoperative bariatric surgery utilization is associated with increased 90-day postoperative complication rates after total joint arthroplasty. J Am Acad Orthop Surg 2019 Sep 16 Long H, Xie D, Zeng C, Wei J, Wang Y, Yang T, Xu B, Qian Y, Li J, Wu Z, Lei G (2019) Association between body composition and osteoarthritis: a systematic review and meta-analysis. Int J Rheum Dis 22(12):2108–2118. https://doi.org/10.1111/1756-185X.13719 Maly R, Costigan PA, Olney SJ (2005) Contribution of psychosocial and mechanical variables to physical performance measures in knee osteoarthritis. Phys Ther 85 (12):1318–1328 McLawhorn AS, Southren D, Wang YC, Marx RG, Dodwell ER (2016) Cost-effectiveness of bariatric surgery prior to total knee arthroplasty in the morbidly obese: a computer model-based evaluation. J Bone Joint Surg Am 98(2):e6. https://doi.org/10.2106/JBJS. N.00416 McLawhorn AS, Levack AE, Lee YY, Ge Y, Do H, Dodwell ER (2018a) Bariatric surgery improves outcomes after lower extremity arthroplasty in the morbidly obese: a propensity score-matched analysis of a new york statewide database. J Arthroplast. 33 (7):2062–2069.e McLawhorn AS, Levack AE, Lee YY, Ge Y, Do H, Dodwell ER (2018b) Bariatric surgery improves outcomes after lower extremity arthroplasty in the morbidly obese: a propensity score-matched analysis of a New York Statewide Database. J Arthroplast 33 (7):2062–2069. e2064. https://doi.org/10.1016/j.arth. 2017.11.056 Moon Han S, Kim WW, Oh JH (2005) Results of laparoscopic sleeve gastrectomy (LSG) at 1 year in morbidly obese Korean patients. Obes Surg 15 (10):1469–1475. https://doi.org/10.1381/ 096089205774859227 Mundermann A, Dyrby CO, Andriacchi TP (2005) Secondary gait changes in patients with medial compartment knee osteoarthritis: increased load at the ankle, knee, and hip during walking. Arthritis Rheum 52 (9):2835–2844. https://doi.org/10.1002/art.21262 Nelson LG, Lopez PP, Haines K, Stefan B, Martin T, Gonzalez R, Byers P, Murr MM (2006) Outcomes of bariatric surgery in patients > or ¼65 years. Surg Obes Relat Dis 2(3):384–388. https://doi.org/10.1016/j. soard.2006.02.012 Nickel BT, Klement MR, Penrose CT, Green CL, Seyler TM, Bolognesi MP (2016) Lingering risk: bariatric surgery before total knee arthroplasty. J Arthroplasty 31(9 Suppl):207–211. https://doi.org/10. 1016/j.arth.2016.02.075

825

Nunez M, Lozano L, Nunez E, Sastre S, Del Val JL, Suso S (2011) Good quality of life in severely obese total knee replacement patients: a case-control study. Obes Surg 21(8):1203–1208. https://doi.org/10.1007/ s11695-010-0197-9 Ogden CL, Carroll MD, Flegal KM (2014) Prevalence of obesity in the United States. JAMA 312(2):189–190. https://doi.org/10.1001/jama.2014.6228 Ponta ML, Gozza M, Giacinto J, Gradaschi R, Adami GF (2014) Effects of obesity on posture and walking: study prior to and following surgically induced weight loss. Obes Surg 24(11):1915–1920. https://doi.org/10. 1007/s11695-014-1254-6 Pozzobon D, Ferreira PH, Blyth FM, Machado GC, Ferreira ML (2018) Can obesity and physical activity predict outcomes of elective knee or hip surgery due to osteoarthritis? A meta-analysis of cohort studies. BMJ Open 8(2):e017689. https://doi.org/10.1136/bmjopen2017-017689 Reyes C, Leyland KM, Peat G, Cooper C, Arden NK, Prieto-Alhambra D (2016) Association between overweight and obesity and risk of clinically diagnosed knee, hip, and hand osteoarthritis: a population-based cohort study. Arthritis Rheumatol 68(8):1869–1875 Runhaar J, Koes BW, Clockaerts S, Bierma-Zeinstra SM (2011) A systematic review on changed biomechanics of lower extremities in obese individuals: a possible role in development of osteoarthritis. Obes Rev 12 (12):1071–1082. https://doi.org/10.1111/j.1467-789X. 2011.00916.x Salih S, Sutton P (2013) Obesity, knee osteoarthritis and knee arthroplasty: a review. BMC Sports Sci Med Rehabil 5(1):25. https://doi.org/10.1186/2052-18475-25 Schwarzkopf R, Lavery JA, Hooper J, Parikh M, Gold HT (2018) Bariatric surgery and time to total joint arthroplasty: does it affect readmission and complication rates? Obes Surg 28(5):1395–1401. https://doi. org/10.1007/s11695-017-3034-6 Sharples AJ, Mahawar K (2019) Systematic review and meta-analysis of randomised controlled trials comparing long-term outcomes of Roux-En-Y gastric bypass and sleeve gastrectomy. Obes Surg Nov 13 Simopoulou T, Malizos KN, Iliopoulos D, Stefanou N, Papatheodorou L, Ioannou M, Tsezou A (2007) Differential expression of leptin and leptin’s receptor isoform (Ob-Rb) mRNA between advanced and minimally affected osteoarthritic cartilage; effect on cartilage metabolism. Osteoarthr Cartil 15 (8):872–883. https://doi.org/10.1016/j.joca.2007.01. 018 Smith TO, Aboelmagd T, Hing CB, MacGregor A (2016) Does bariatric surgery prior to total hip or knee arthroplasty reduce post-operative complications and improve clinical outcomes for obese patients? Systematic review and meta-analysis. Bone Joint J 98-B (9):1160–1166. https://doi.org/10.1302/0301-620X. 98B9.38024

826 Sowers MR, Karvonen-Gutierrez CA (2010) The evolving role of obesity in knee osteoarthritis. Curr Opin Rheumatol 22(5):533–537. https://doi.org/10.1097/ BOR.0b013e32833b4682 Springer BD, Carter JT, McLawhorn AS, Scharf K, Roslin M, Kallies KJ, Morton JM, Kothari SN (2017) Obesity and the role of bariatric surgery in the surgical management of osteoarthritis of the hip and knee: a review of the literature. Surg Obes Relat Dis 13 (1):111–118. https://doi.org/10.1016/j.soard.2016.09. 011 Stavrakis AI, Khoshbin A, McLawhorn AS, Parks ML (2018) Bariatric surgery prior to total joint arthroplasty, does it decrease the risk of obesity related perioperative complications? Curr Rheumatol Rep 20(2):7. https:// doi.org/10.1007/s11926-018-0717-5 Sturm R, Hattori A (2013) Morbid obesity rates continue to rise rapidly in the United States. Int J Obes 37 (6):889–891. https://doi.org/10.1038/ijo.2012.159 Surgical Weight-Loss to Improve Functional Status Trajectories Following Total Knee Arthroplasty (SWIFT Trial) (n.d.). https://clinicaltrials.gov/ct2/ show/NCT02598531. Accessed December 25 2019 Taylor WR, Heller MO, Bergmann G, Duda GN (2004) Tibio-femoral loading during human gait and stair climbing. J Orthop Res 22(3):625–632. https://doi. org/10.1016/j.orthres.2003.09.003 Teichtahl AJ, Wluka AE, Wang Y, Hanna F, English DR, Giles GG, Cicuttini FM (2009) Obesity and adiposity are associated with the rate of patella cartilage volume loss over 2 years in adults without knee osteoarthritis. Ann Rheum Dis 68(6):909–913. https://doi.org/10. 1136/ard.2008.093310 Tohidi M, Brogly SB, Lajkosz K, Harrison MM, Campbell AR, VanDenKerkhof E, Mann SM (2019) Ten-year

K. M. Mellion and S. N. Kothari risk of complication and mortality after total hip arthroplasty in morbidly obese patients: a population study. Can J Surg 62(6):442–449 Vartiainen P, Bragge T, Lyytinen T, Hakkarainen M, Karjalainen PA, Arokoski JP (2012) Kinematic and kinetic changes in obese gait in bariatric surgeryinduced weight loss. J Biomech 45(10):1769–1774. https://doi.org/10.1016/j.jbiomech.2012.05.002 Vincent HK, Ben-David K, Conrad BP, Lamb KM, Seay AN, Vincent KR (2012) Rapid changes in gait, musculoskeletal pain, and quality of life after bariatric surgery. Surg Obes Relat Dis 8(3):346–354. https:// doi.org/10.1016/j.soard.2011.11.020 Wang H, Bai J, He B, Hu X, Liu D (2016) Osteoarthritis and the risk of cardiovascular disease: a meta-analysis of observational studies. Sci Rep 6:39672 Watts CD, Houdek MT, Wagner ER, Lewallen DG, Mabry TM (2016) Morbidly obese vs nonobese aseptic revision total hip arthroplasty: surprisingly similar outcomes. J Arthroplast 31(4):842–845. https://doi. org/10.1016/j.arth.2015.08.036 Workgroup of the American Association of Hip and Knee Surgeons Evidence Based Committee (2013) Obesity and total joint arthroplasty: a literature based review. J Arthroplast 28(5):714–721. https://doi.org/10.1016/j. arth.2013.02.011 Yokota RT, Van der Heyden J, Demarest S, Tafforeau J, Nusselder WJ, Deboosere P et al (2015) Contribution of chronic diseases to the mild and severe disability burden in Belgium. Arch Public Health 73(1):37 Zusmanovich M, Kester BS, Schwarzkopf R (2018) Postoperative complications of total joint arthroplasty in obese patients stratified by BMI. J Arthroplast 33 (3):856–864

Relapse of Diabetes After Metabolic/ Bariatric Surgery

61

Lívia Porto Cunha da Silveira, Tarissa Zanata Petry, and Ricardo Vitor Cohen

Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 827 Pathogenesis of T2D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 828 How to Predict Metabolic/Bariatric Surgery Outcomes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 828 Predictive Scores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 829 Revisional Bariatric and Metabolic Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 830 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 832

Abstract

The use of nonclinical but also laboratory tools to predict type 2 diabetes (T2D) remission after metabolic/bariatric surgery has been extensively researched. Basal fasting C-peptide level is an accessible test, but it cannot predict the chances of remission alone and is biased in patients with more severe diabetes. So, other robust biological and clinical predictors of T2D remission after surgery have been proposed. After assessing the predictive factors and acknowledging the risk of non-remission and relapse, a pathway to adequate clinical management is necessary, L. P. C. da Silveira · T. Z. Petry Endocrinologist, Center for Obesity and Diabetes, Oswaldo Cruz German Hospital, São Paulo, SP, Brazil R. Vitor Cohen (*) Center for Obesity and Diabetes, Oswaldo Cruz German Hospital, São Paulo, SP, Brazil e-mail: [email protected]

particularly for cases with recurrent T2D. Revisional surgery has been widely discussed as an option for those cases, despite the lack of robust evidence. Interestingly, inadequate weight loss or weight regain that usually indicates the reoperation is not always linked with T2D recurrence. Pharmacological agents such as GLP1 analogs may be an add-on alternative to reach glycemic control, if revisional surgery is insufficient. Keywords

Relapsing diabetes · Recurrent diabetes · Predictive scores · Sleeve gastrectomy · Diabetes remission · Incretins

Introduction Type 2 Diabetes mellitus (T2D) is a chronic and progressive disease characterized by

# Springer Nature Switzerland AG 2020 J. Faintuch and S. Faintuch (eds.), Obesity and Diabetes, https://doi.org/10.1007/978-3-030-53370-0_61

827

828

hyperglycemia, insulin resistance, and relative impairment of insulin secretion. It is strongly associated with obesity in all ethnic groups (Mokdad et al. 2001). The prevalence of T2D is increasing worldwide. The relationship between this disease and obesity is well-established as 80% of T2D patients are overweight or obese (Schauer et al. 2012). As a multifactorial disease, understanding its pathogenesis and its treatment is challenging. Although insulin resistance can be traced back to its genetic background, the epidemic of diabetes is related to the epidemic of obesity and physical inactivity as both are insulin-resistant states (Sha and Laferrère 2017).

L. P. C. da Silveira et al.

cells (accelerated lipolysis), gastrointestinal tract (incretin deficiency/resistance), alfa cells (hyperglucagonemia), kidney (increased glucose reabsorption), and brain (insulin resistance). As complex as the pathogenesis, the treatment of this disease is also challenging. Randomized clinical trials have indicated that metabolic/bariatric surgery achieves rapid and better glycemic control than medical therapy alone in obese patients with T2D. Accordingly, metabolic/bariatric surgery is recommended in the treatment algorithm of T2D in patients with a body mass index of 30 kg/m2 and over and endorsed by over 50 worldwide medical and scientific associations (Rubino et al. 2017).

Pathogenesis of T2D

How to Predict Metabolic/Bariatric Surgery Outcomes

It is currently known that eight factors play a role in the development of glucose intolerance in T2D individuals (DeFronzo 2009). Genetically, individuals prone to develop T2D evolve to insulin resistance that presents itself in multiple organs. In the liver, it leads to an overproduction of glucose, despite fasting hyperinsulinemia and by reduced suppression of hepatic glucose production in response to insulin. In the muscle, it decreases glucose uptake after carbohydrate ingestion resulting in postprandial hyperglycemia. Thus, decreased insulin sensitivity stimulates insulin production by the pancreatic ß-cells. Over time, the ß-cells become fatigued, losing function progressively and reducing circulating insulin levels, consequently increasing plasma glucose concentration leading to the onset of diabetes. In addition to the muscle, liver, and ß-cell, several other cellular dysfunctions are part of T2D pathogenesis, with the involvemet of fat

As the goals of metabolic/bariatric surgery are the control of T2D and related metabolic conditions, high remission rates are expected. Due to the use of different remission criteria, rates are very variable in the literature. The rate of T2D remission varies from 24% to 95% at 2 years, depending on the type of surgery, the definition of remission, and the characteristics of patients enrolled in the studies (Yan et al. 2017; Maleckas et al. 2015). The main goal of metabolic/bariatric surgery, as described above, is to keep the American Diabetes Association (ADA) triple endpoint under control (Table 61.1) (Standards of Medical Care in Diabetes 2020). Therefore, as T2D is a progressive disease, the ADA are targeted with the correct association of surgery and the best medical treatment available. Several studies tried to identify the best protocols to manage these patients peri and postoperatively (Sjostrom 2013). The main objectives

Table 61.1 Summary of the American Diabetes Association for glycemic, blood pressure, and lipid control for adults with diabetes (Standards of Medical Care in Diabetes 2020) A1c Blood Pressure Lipids LDL cholesterol

0.05), diabetes (73.7 vs. 79%; p > 0.05), and obstructive sleep apnea syndrome (100 vs. 97%; p > 0.05) was similar between groups. Differently from previous data, this study showed that the revisional procedure was as safe as the primary one and showed similar significant improvement in comorbidities, as T2D, even with less weight loss. Finally, a systematic review and meta-analysis published in 2018 (Pędziwiatr et al. 2018) assessed 21 studies comparing outcomes after primary versus revisional RYGB and included 11,720 and 3043 patients, respectively. Seven studies reported results on T2D and hypertension remission, and there were no differences between groups ( p ¼ 0.61). It is important to notice that the majority of patients in the revisional group had a VBG or AGB as the primary procedure. Weight loss was significant in the primary RYGB group (20% more excess weight loss than revisions). The analysis showed higher rates of morbidity and mortality in revisional procedures, although the numbers are still relatively low (0.2 versus 0.6% of mortality). However, there were no differences in the case-matched subgroup. Revisional surgery for Type 2 diabetes relapse still lacks quality data. Keeping in mind that T2D is a chronic and progressive disease, maintaining glycemic endpoints under the target is important to prevent micro and macrovascular complications. Metabolic surgery is recommended when the best medical treatment fails. However, the optimal strategy to mitigate recurrence, analog to cancer treatment, when oncological surgery is often associated to radio/ chemotherapy, is to keep the best medical treatment after surgery. So far, there are no accurate scores to predict T2D outcomes after metabolic interventions. Those available are good tools to help the clinician to refer the best patients to surgery.

832

Operations that reroute the food through the gastrointestinal tract deliver long-term better outcomes than those that don’t. Currently, based on the mechanisms behind the “bypass” operations, it seems that converting SG or AGB to RYGB or DS is efficacious to achieve glycemic control and added weight loss, but always keeping along the best medical treatment. In most cases of postoperative T2D recurrence after RYGB or DS, if there is no anatomical complication to be fixed (as gastro-gastric fistulas), adding pharmacological agents as GLP1 analogs may be an alternative to reach glycemic control.

References Aleassa EM, Hassan M, Hayes K, Brethauer SA, Schauer PR, Aminian A (2019) Effect of revisional bariatric surgery on type 2 diabetes mellitus. Surg Endosc 33 (8):2642–2648 Arterburn DE, Bogart A, Sherwood NE et al (2013a January) A multisite study of long-term remission and relapse of type 2 diabetes mellitus following gastric bypass. Obes Surg 23(1):93–102 Arterburn DE, Bogart A, Sherwood NE et al (2013b) A multisite study of long-term remission and relapse of type 2 diabetes mellitus following gastric bypass. Obes Surg 23:93–102 Brethauer SA, Aminian A, Romero-Talamás H et al (2013) Can diabetes be surgically cured? Long-term metabolic effects of bariatric surgery in obese patients with type 2 diabetes mellitus. Ann Surg 258:628–636 Ceperuelo-Mallafre V, Llaurado G, Keiran N et al (2019 Oct) Preoperative circulating succinate levels as a biomarker for diabetes remission after bariatric surgery. Diabetes Care 42(10):1956–1965 Ciudin A, Fidilio E, Ortiz A et al (2019 Jul) Genetic testing to predict weight loss and diabetes remission and longterm sustainability after bariatric surgery: a pilot study. J Clin Med 8(7):964 Cohen RV, Pereira TV, Aboud CM et al (2017) Microvascular Outcomes after Metabolic Surgery (MOMS) in patients with type 2 diabetes mellitus and class I obesity: rationale and design for a randomized controlled trial. BMJ Open 7:e013574 DeFronzo RA (2009 Apr) From the triumvirate to the ominous octet: a new paradigm for the treatment of type 2 diabetes mellitus. Diabetes 58(4):773–795 Dixon JB, Chuang LM, Chong K et al (2013 Jan) Predicting the glycemic response to gastric bypass surgery in patients with type 2 diabetes. Diabetes Care 36(1):20–26

L. P. C. da Silveira et al. Gloy VL, Briel M, Bhatt DL et al (2013) Bariatric Surgery versus non-surgery treatment for obesity: a systematic review and meta-analysis of randomized controlled trials. BMJ 347:f5934 Maleckas A, Venclauskas L, Wallenius V et al (2015 Mar) Surgery in the treatment of type 2 diabetes mellitus. Scand J Surg 104(1):40–47 Mingrone G, Panunzi S, De Gaetano A, Guidone C, Iaconelli A, Leccesi L, Nanni G, Pomp A, Castagneto M, Ghirlanda G, Rubino F (2012) Bariatric surgery versus conventional medical therapy for type 2 diabetes. N Engl J Med 366:1577–1585 Mingrone G, Panunzi S, De Gaetano A et al (2015) Bariatric–metabolic surgery versus conventional medical treatment in obese patients with type 2 diabetes: 5 year follow-up of an open-label, single-centre, randomized controlled trial. Lancet 386:964–973 Miras AD, Pérez-Pevida B, Aldhwayan M et al (2019) Adjunctive liraglutide treatment in patients with persistent or recurrent type 2 diabetes after metabolic surgery (GRAVITAS): a randomised, double-blind, placebocontrolled trial. Lancet Diabetes Endocrinol Mokdad AH, Bowman BA, Ford ES et al (2001) The continuing epidemics of obesity and diabetes in the United States. JAMA 286:1195–1200 Mor A, Keenan E, Portenier D, Torquati A (2013) Casematched analysis comparing outcomes of revisional versus primary laparoscopic Roux-en-Y gastric bypass. Surg Endosc 27:548–552 Oliveira VLP, Martins GP, Mottin CC et al (2018 Jan) Predictors of long-term remission and relapse of type 2 diabetes mellitus following gastric bypass in severely obese patients. Obes Surg 28(1):195–203 Panunzi S, De Gaetano A, Carnicelli A, Mingrone G (2015) Predictors of remission of diabetes mellitus in severely obese individuals undergoing bariatric surgery: do BMI or procedure choice matter? Ann Surg 261:459–467 Pędziwiatr M, Malczak P, Wierdak M et al (2018) Revisional Gastric bypass is inferior to primary gastric bypass in terms of short- and long-term outcomes— systematic review and meta-analysis. Obes Surg 28:2083–2091 Pucci A, Tymoszuk U, Cheung WH et al (2018 Mar) Type 2 diabetes remission 2 years post Roux-en-Y gastric bypass and sleeve gastrectomy: the role of the weight loss and comparison of DiaRem and DiaBetter scores. Diabet Med 35(3):360–367 Rubino F, Nathan DM, Eckel RH et al (2017) Metabolic surgery in the treatment algorithm for type 2 diabetes: a joint statement by international diabetes organizations. Obes Surg 27:2–21 Schauer PR, Kashyap SR, Wolski K et al (2012) Bariatric surgery versus intensive medical therapy in obese patients with diabetes. N Engl J Med 366:1567–1576 Schauer PR, Bhatt DL, Kirwan JP et al (2014) STAMPEDE investigators. Bariatric surgery versus intensive medical therapy for diabetes—3-year outcomes. N Engl J Med 370:2002–2013

61

Relapse of Diabetes After Metabolic/Bariatric Surgery

Sha A, Laferrère B (2017 Aug) Diabetes after bariatric surgery. Can J Diabetes 41(4):401–406 Sjostrom L (2013) Review of the key results from the Swedish obese Subjects (SoS) trial—a prospective controlled intervention study of bariatric surgery. J Intern Med 273:219–234 Standards of Medical Care in Diabetes—2020—American Diabetes Association—Diabetes care Diabetes Care 2020 Jan; 43(Suppl. 1):S1–S2 Still CD, Wood GC, Benotti P et al (2014) Preoperative prediction of type 2 diabetes remission after Roux-enY gastric bypass surgery: a retrospective cohort study. Lancet Diabetes Endocrinol 2:38–45 Still CD, Benotti P, Mirshahi T et al (2019 May) DiaRem2: incorporating duration of diabetes to

833 improve prediction of diabetes remission after metabolic surgery. Surg Obes Relat Dis 15(5):717–724 Sudan R, Nguyen NT, Hutter MM, Brethauer SA, Ponce J, Morton JM (2014) Morbidity, mortality, and weight loss outcomes after reoperative bariatric surgery in the USA. J Gastrointest Surg 19(1):171–178 Vallois A, Menahem B, Le Roux Y et al (2019) Revisional Roux-en-Y Gastric bypass: a safe surgical opportunity? Results of a case-matched study. Obes Surg 29:903–910 Yan J, Cohen R, Aminian A (2017) Reoperative bariatric surgery for treatment of type 2 diabetes mellitus. Surg Obes Relat Dis 00–00

Malnutrition in Obesity

62

Sonmoon Mohapatra and Capecomorin S. Pitchumoni

Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 836 Deficiencies Across All Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 836 Definition of Obesity and Its Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 836 Metabolic Obesity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 836 Obesity and Muscle Wasting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 837 Types of Bariatric Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 837 Nutritional Deficiencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 837 Deficiencies Post-Bariatric Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 838 Nutritional Deficiencies Before and After Bariatric Management . . . . . . . . . . . . . . . . . 838 Protein . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Essential Fatty Acids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vitamin D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vitamin B1 (Thiamine) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vitamin B12 and Folate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vitamins A, C, E, K . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Iron . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Zinc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Copper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

838 838 841 842 843 843 843 844 844

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 845 S. Mohapatra Department of Gastroenterology and Hepatology, Saint Peter’s University Hospital – Rutgers Robert Wood Johnson School of Medicine, New Brunswick, NJ, USA C. S. Pitchumoni (*) Department of Gastroenterology, Hepatology and Clinical Nutrition, Saint Peter’s University Hospital – Rutgers Robert Wood Johnson School of Medicine, New Brunswick, NJ, USA New York Medical College, Valhalla, NY, USA Robert Wood Johnson School of Medicine, Rutgers University, New Brunswick, NJ, USA e-mail: [email protected] # Springer Nature Switzerland AG 2020 J. Faintuch and S. Faintuch (eds.), Obesity and Diabetes, https://doi.org/10.1007/978-3-030-53370-0_62

835

836

Abstract

Obesity and malnutrition appear to be at the opposite ends of the spectrum. But in reality, obesity in itself is a form of malnutrition associated with nutritional deficiencies. Attempts to lose weight by various special diets complement the preexisting nutritional deficiencies. Bariatric surgical procedures are well-accepted for sustained remission of obesity. The physiological basis of these procedures is either gastric reduction (restrictive) or diminished absorption of nutrients (malabsorptive). In both types, the weight loss is associated with worsening of the preexisting nutrient deficiencies or creating new deficiencies of macro- and micronutrients. A well-defined protocol-based pre- and postoperative nutritional assessment is needed for minimal adverse effects. Clinical guidelines and recommendations are provided in the present chapter. Keywords

Obesity · Bariatric surgery · Roux-en-Y gastric bypass · Sleeve gastrectomy · Biliopancreatic bypass with duodenal switch · Micronutrients · Vitamin B12 · Folate (vitamin B9) Vitamin B1 · Thiamine · Biotin · Wernicke’s psychosis · Osteomalacia · Osteoporosis · Blind loop syndrome · SIBO · Anemia · Neuropathy · Magnesium · Copper · Selenium

Introduction Obesity and malnutrition are presently considered as two sides of one crisis or “a double burden of malnutrition,” the coexistence of nutritional deficiencies along with overweight and obesity. A recent study has projected that nearly 1 in 2 US adults will be obese by 2030 (Ward et al. 2019). It also showed that severe obesity would affect nearly 1 in 4 adults by 2030, particularly women and certain disadvantaged populations. China and India also are facing the obesity crisis, especially in the middle and upper class,

S. Mohapatra and C. S. Pitchumoni

contrasting with a malnourished poor.

high

prevalence

of

Deficiencies Across All Classes A dogmatic view of the past is that malnutrition is the consequence of the chronic consumption of an insufficient quantity of inferior quality diet as a result of poverty or disease. However, it has become clear that malnutrition does not spare the rich. The excessive use of high calorie foods and drinks along with sedentarism is relevant. The available solutions to the problem of obesity are many, including various calorie-restricted diets and bariatric surgical procedures designed to induce malabsorption. All of the above cause malnutrition and malabsorption of nutrients with varying amounts as side effects.

Definition of Obesity and Its Types In several Asiatic countries, BMI of 23.0–24.9 kg/m2 and
25 kg/m2 are adopted for overweight and obesity, respectively (World Health Organization 2014; Gronroos et al. 2010; Misra et al. 2009). The traditional WHO classification is predominantly applicable to the people of European ancestry. Abdominal fat accumulation has a more ominous prognosis than gluteo-femoral fat, raising doubts about reliability of BMI alone (Adab et al. 2018; Kissebah et al. 1982; Després et al. 1990). Even visceral fat signals cardiovascular complications at different proportions among Asians and other Americans (Demerath et al. 2007; Lim et al. 2011).

Metabolic Obesity New clinical modalities encompassing metabolically healthy but obese (MHO), metabolically obese but normal weight (MONW), and metabolic or central obesity have thus been devised (Karelis et al. 2004; Hamdy et al. 2006). A normal waist to hip ratio (< 0.95 for men, < 0.86 for

62

Malnutrition in Obesity

837

women) rules out metabolic obesity. Based on waist-hip ratio, obesity is classified as pearshaped when the waist-hip ratio is